Date: Wed, 7 Apr 2010 08:50:05 GMT From: "Andrei V. Lavreniyuk" <andy.lavr@reactor-xg.kiev.ua> To: gecko@FreeBSD.org Subject: Re: ports/145450: [ERROR] cannot compile www/firefox version 3.6.3 Message-ID: <201004070850.o378o5ff085642@freefall.freebsd.org>
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The following reply was made to PR ports/145450; it has been noted by GNATS.
From: "Andrei V. Lavreniyuk" <andy.lavr@reactor-xg.kiev.ua>
To: bug-followup@FreeBSD.org
Cc: gecko@FreeBSD.org, Florian Smeets <flo@smeets.im>
Subject: Re: ports/145450: [ERROR] cannot compile www/firefox version 3.6.3
Date: Wed, 07 Apr 2010 11:48:12 +0300
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07.04.2010 11:26, Florian Smeets пишет:
>> show me the output of python -V and pkg_info|grep python?
>>
>
> Sorry, there is a "can you please" missing. Did not want to sound as
> harsh as it seems.
>
> So, can you please show me the output? :-)
:)
Workaround:
# portupgrade -f boost-python-libs-1.41.0 py26-notify-0.1.1_7 python26-2.6.4
+
Attached patch.
--
Best regards, Andrei V. Lavreniyuk.
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--- xpcom/idl-parser/header.py.orig 2010-04-02 19:03:13.000000000 +0300
+++ xpcom/idl-parser/header.py 2010-04-07 11:23:45.088650024 +0300
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/local/bin/python
# header.py - Generate C++ header files from IDL.
#
# ***** BEGIN LICENSE BLOCK *****
--------------080004000200030807030507
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filename="patch-ply"
diff -ruN ply.orig/lex.py ply/lex.py
--- other-licenses/ply/ply.orig/lex.py 2010-04-02 19:02:56.000000000 +0300
+++ other-licenses/ply/ply/lex.py 2009-08-27 04:28:42.000000000 +0300
@@ -1,45 +1,61 @@
# -----------------------------------------------------------------------------
# ply: lex.py
#
-# Author: David M. Beazley (dave@dabeaz.com)
+# Copyright (C) 2001-2009,
+# David M. Beazley (Dabeaz LLC)
+# All rights reserved.
#
-# Copyright (C) 2001-2008, David M. Beazley
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+# * Neither the name of the David Beazley or Dabeaz LLC may be used to
+# endorse or promote products derived from this software without
+# specific prior written permission.
#
-# This library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 2.1 of the License, or (at your option) any later version.
-#
-# This library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-# Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public
-# License along with this library; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-#
-# See the file COPYING for a complete copy of the LGPL.
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
# -----------------------------------------------------------------------------
-__version__ = "2.5"
-__tabversion__ = "2.4" # Version of table file used
+__version__ = "3.3"
+__tabversion__ = "3.2" # Version of table file used
import re, sys, types, copy, os
-# This regular expression is used to match valid token names
-_is_identifier = re.compile(r'^[a-zA-Z0-9_]+$')
-
-# _INSTANCETYPE sets the valid set of instance types recognized
-# by PLY when lexers are defined by a class. In order to maintain
-# backwards compatibility with Python-2.0, we have to check for
-# the existence of ObjectType.
-
+# This tuple contains known string types
try:
- _INSTANCETYPE = (types.InstanceType, types.ObjectType)
+ # Python 2.6
+ StringTypes = (types.StringType, types.UnicodeType)
except AttributeError:
- _INSTANCETYPE = types.InstanceType
- class object: pass # Note: needed if no new-style classes present
+ # Python 3.0
+ StringTypes = (str, bytes)
+
+# Extract the code attribute of a function. Different implementations
+# are for Python 2/3 compatibility.
+
+if sys.version_info[0] < 3:
+ def func_code(f):
+ return f.func_code
+else:
+ def func_code(f):
+ return f.__code__
+
+# This regular expression is used to match valid token names
+_is_identifier = re.compile(r'^[a-zA-Z0-9_]+$')
# Exception thrown when invalid token encountered and no default error
# handler is defined.
@@ -49,35 +65,50 @@
self.args = (message,)
self.text = s
-# An object used to issue one-time warning messages for various features
-
-class LexWarning(object):
- def __init__(self):
- self.warned = 0
- def __call__(self,msg):
- if not self.warned:
- sys.stderr.write("ply.lex: Warning: " + msg+"\n")
- self.warned = 1
-
-_SkipWarning = LexWarning() # Warning for use of t.skip() on tokens
-
# Token class. This class is used to represent the tokens produced.
class LexToken(object):
def __str__(self):
return "LexToken(%s,%r,%d,%d)" % (self.type,self.value,self.lineno,self.lexpos)
def __repr__(self):
return str(self)
- def skip(self,n):
- self.lexer.skip(n)
- _SkipWarning("Calling t.skip() on a token is deprecated. Please use t.lexer.skip()")
+
+# This object is a stand-in for a logging object created by the
+# logging module.
+
+class PlyLogger(object):
+ def __init__(self,f):
+ self.f = f
+ def critical(self,msg,*args,**kwargs):
+ self.f.write((msg % args) + "\n")
+
+ def warning(self,msg,*args,**kwargs):
+ self.f.write("WARNING: "+ (msg % args) + "\n")
+
+ def error(self,msg,*args,**kwargs):
+ self.f.write("ERROR: " + (msg % args) + "\n")
+
+ info = critical
+ debug = critical
+
+# Null logger is used when no output is generated. Does nothing.
+class NullLogger(object):
+ def __getattribute__(self,name):
+ return self
+ def __call__(self,*args,**kwargs):
+ return self
# -----------------------------------------------------------------------------
-# Lexer class
+# === Lexing Engine ===
#
-# This class encapsulates all of the methods and data associated with a lexer.
+# The following Lexer class implements the lexer runtime. There are only
+# a few public methods and attributes:
#
# input() - Store a new string in the lexer
# token() - Get the next token
+# clone() - Clone the lexer
+#
+# lineno - Current line number
+# lexpos - Current position in the input string
# -----------------------------------------------------------------------------
class Lexer:
@@ -105,7 +136,6 @@
self.lexliterals = "" # Literal characters that can be passed through
self.lexmodule = None # Module
self.lineno = 1 # Current line number
- self.lexdebug = 0 # Debugging mode
self.lexoptimize = 0 # Optimized mode
def clone(self,object=None):
@@ -145,6 +175,7 @@
filename = os.path.join(outputdir,basetabfilename)+".py"
tf = open(filename,"w")
tf.write("# %s.py. This file automatically created by PLY (version %s). Don't edit!\n" % (tabfile,__version__))
+ tf.write("_tabversion = %s\n" % repr(__version__))
tf.write("_lextokens = %s\n" % repr(self.lextokens))
tf.write("_lexreflags = %s\n" % repr(self.lexreflags))
tf.write("_lexliterals = %s\n" % repr(self.lexliterals))
@@ -184,7 +215,16 @@
if isinstance(tabfile,types.ModuleType):
lextab = tabfile
else:
- exec "import %s as lextab" % tabfile
+ if sys.version_info[0] < 3:
+ exec("import %s as lextab" % tabfile)
+ else:
+ env = { }
+ exec("import %s as lextab" % tabfile, env,env)
+ lextab = env['lextab']
+
+ if getattr(lextab,"_tabversion","0.0") != __version__:
+ raise ImportError("Inconsistent PLY version")
+
self.lextokens = lextab._lextokens
self.lexreflags = lextab._lexreflags
self.lexliterals = lextab._lexliterals
@@ -196,7 +236,7 @@
titem = []
txtitem = []
for i in range(len(lre)):
- titem.append((re.compile(lre[i][0],lextab._lexreflags),_names_to_funcs(lre[i][1],fdict)))
+ titem.append((re.compile(lre[i][0],lextab._lexreflags | re.VERBOSE),_names_to_funcs(lre[i][1],fdict)))
txtitem.append(lre[i][0])
self.lexstatere[key] = titem
self.lexstateretext[key] = txtitem
@@ -211,8 +251,8 @@
def input(self,s):
# Pull off the first character to see if s looks like a string
c = s[:1]
- if not (isinstance(c,types.StringType) or isinstance(c,types.UnicodeType)):
- raise ValueError, "Expected a string"
+ if not isinstance(c,StringTypes):
+ raise ValueError("Expected a string")
self.lexdata = s
self.lexpos = 0
self.lexlen = len(s)
@@ -221,8 +261,8 @@
# begin() - Changes the lexing state
# ------------------------------------------------------------
def begin(self,state):
- if not self.lexstatere.has_key(state):
- raise ValueError, "Undefined state"
+ if not state in self.lexstatere:
+ raise ValueError("Undefined state")
self.lexre = self.lexstatere[state]
self.lexretext = self.lexstateretext[state]
self.lexignore = self.lexstateignore.get(state,"")
@@ -255,7 +295,7 @@
self.lexpos += n
# ------------------------------------------------------------
- # token() - Return the next token from the Lexer
+ # opttoken() - Return the next token from the Lexer
#
# Note: This function has been carefully implemented to be as fast
# as possible. Don't make changes unless you really know what
@@ -299,10 +339,6 @@
lexpos = m.end()
- # if func not callable, it means it's an ignored token
- if not callable(func):
- break
-
# If token is processed by a function, call it
tok.lexer = self # Set additional attributes useful in token rules
@@ -319,9 +355,9 @@
# Verify type of the token. If not in the token map, raise an error
if not self.lexoptimize:
- if not self.lextokens.has_key(newtok.type):
- raise LexError, ("%s:%d: Rule '%s' returned an unknown token type '%s'" % (
- func.func_code.co_filename, func.func_code.co_firstlineno,
+ if not newtok.type in self.lextokens:
+ raise LexError("%s:%d: Rule '%s' returned an unknown token type '%s'" % (
+ func_code(func).co_filename, func_code(func).co_firstlineno,
func.__name__, newtok.type),lexdata[lexpos:])
return newtok
@@ -348,60 +384,60 @@
newtok = self.lexerrorf(tok)
if lexpos == self.lexpos:
# Error method didn't change text position at all. This is an error.
- raise LexError, ("Scanning error. Illegal character '%s'" % (lexdata[lexpos]), lexdata[lexpos:])
+ raise LexError("Scanning error. Illegal character '%s'" % (lexdata[lexpos]), lexdata[lexpos:])
lexpos = self.lexpos
if not newtok: continue
return newtok
self.lexpos = lexpos
- raise LexError, ("Illegal character '%s' at index %d" % (lexdata[lexpos],lexpos), lexdata[lexpos:])
+ raise LexError("Illegal character '%s' at index %d" % (lexdata[lexpos],lexpos), lexdata[lexpos:])
self.lexpos = lexpos + 1
if self.lexdata is None:
- raise RuntimeError, "No input string given with input()"
+ raise RuntimeError("No input string given with input()")
return None
+ # Iterator interface
+ def __iter__(self):
+ return self
+
+ def next(self):
+ t = self.token()
+ if t is None:
+ raise StopIteration
+ return t
+
+ __next__ = next
+
# -----------------------------------------------------------------------------
-# _validate_file()
+# ==== Lex Builder ===
#
-# This checks to see if there are duplicated t_rulename() functions or strings
-# in the parser input file. This is done using a simple regular expression
-# match on each line in the given file. If the file can't be located or opened,
-# a true result is returned by default.
+# The functions and classes below are used to collect lexing information
+# and build a Lexer object from it.
# -----------------------------------------------------------------------------
-def _validate_file(filename):
- import os.path
- base,ext = os.path.splitext(filename)
- if ext != '.py': return 1 # No idea what the file is. Return OK
+# -----------------------------------------------------------------------------
+# get_caller_module_dict()
+#
+# This function returns a dictionary containing all of the symbols defined within
+# a caller further down the call stack. This is used to get the environment
+# associated with the yacc() call if none was provided.
+# -----------------------------------------------------------------------------
+def get_caller_module_dict(levels):
try:
- f = open(filename)
- lines = f.readlines()
- f.close()
- except IOError:
- return 1 # Couldn't find the file. Don't worry about it
-
- fre = re.compile(r'\s*def\s+(t_[a-zA-Z_0-9]*)\(')
- sre = re.compile(r'\s*(t_[a-zA-Z_0-9]*)\s*=')
-
- counthash = { }
- linen = 1
- noerror = 1
- for l in lines:
- m = fre.match(l)
- if not m:
- m = sre.match(l)
- if m:
- name = m.group(1)
- prev = counthash.get(name)
- if not prev:
- counthash[name] = linen
- else:
- print >>sys.stderr, "%s:%d: Rule %s redefined. Previously defined on line %d" % (filename,linen,name,prev)
- noerror = 0
- linen += 1
- return noerror
+ raise RuntimeError
+ except RuntimeError:
+ e,b,t = sys.exc_info()
+ f = t.tb_frame
+ while levels > 0:
+ f = f.f_back
+ levels -= 1
+ ldict = f.f_globals.copy()
+ if f.f_globals != f.f_locals:
+ ldict.update(f.f_locals)
+
+ return ldict
# -----------------------------------------------------------------------------
# _funcs_to_names()
@@ -466,7 +502,7 @@
lexindexfunc[i] = (None, toknames[f])
return [(lexre,lexindexfunc)],[regex],[lexindexnames]
- except Exception,e:
+ except Exception:
m = int(len(relist)/2)
if m == 0: m = 1
llist, lre, lnames = _form_master_re(relist[:m],reflags,ldict,toknames)
@@ -486,319 +522,446 @@
nonstate = 1
parts = s.split("_")
for i in range(1,len(parts)):
- if not names.has_key(parts[i]) and parts[i] != 'ANY': break
+ if not parts[i] in names and parts[i] != 'ANY': break
if i > 1:
states = tuple(parts[1:i])
else:
states = ('INITIAL',)
if 'ANY' in states:
- states = tuple(names.keys())
+ states = tuple(names)
tokenname = "_".join(parts[i:])
return (states,tokenname)
+
# -----------------------------------------------------------------------------
-# lex(module)
+# LexerReflect()
#
-# Build all of the regular expression rules from definitions in the supplied module
+# This class represents information needed to build a lexer as extracted from a
+# user's input file.
# -----------------------------------------------------------------------------
-def lex(module=None,object=None,debug=0,optimize=0,lextab="lextab",reflags=0,nowarn=0,outputdir=""):
- global lexer
- ldict = None
- stateinfo = { 'INITIAL' : 'inclusive'}
- error = 0
- files = { }
- lexobj = Lexer()
- lexobj.lexdebug = debug
- lexobj.lexoptimize = optimize
- global token,input
+class LexerReflect(object):
+ def __init__(self,ldict,log=None,reflags=0):
+ self.ldict = ldict
+ self.error_func = None
+ self.tokens = []
+ self.reflags = reflags
+ self.stateinfo = { 'INITIAL' : 'inclusive'}
+ self.files = {}
+ self.error = 0
- if nowarn: warn = 0
- else: warn = 1
+ if log is None:
+ self.log = PlyLogger(sys.stderr)
+ else:
+ self.log = log
- if object: module = object
+ # Get all of the basic information
+ def get_all(self):
+ self.get_tokens()
+ self.get_literals()
+ self.get_states()
+ self.get_rules()
+
+ # Validate all of the information
+ def validate_all(self):
+ self.validate_tokens()
+ self.validate_literals()
+ self.validate_rules()
+ return self.error
+
+ # Get the tokens map
+ def get_tokens(self):
+ tokens = self.ldict.get("tokens",None)
+ if not tokens:
+ self.log.error("No token list is defined")
+ self.error = 1
+ return
- if module:
- # User supplied a module object.
- if isinstance(module, types.ModuleType):
- ldict = module.__dict__
- elif isinstance(module, _INSTANCETYPE):
- _items = [(k,getattr(module,k)) for k in dir(module)]
- ldict = { }
- for (i,v) in _items:
- ldict[i] = v
- else:
- raise ValueError,"Expected a module or instance"
- lexobj.lexmodule = module
+ if not isinstance(tokens,(list, tuple)):
+ self.log.error("tokens must be a list or tuple")
+ self.error = 1
+ return
+
+ if not tokens:
+ self.log.error("tokens is empty")
+ self.error = 1
+ return
- else:
- # No module given. We might be able to get information from the caller.
- try:
- raise RuntimeError
- except RuntimeError:
- e,b,t = sys.exc_info()
- f = t.tb_frame
- f = f.f_back # Walk out to our calling function
- if f.f_globals is f.f_locals: # Collect global and local variations from caller
- ldict = f.f_globals
- else:
- ldict = f.f_globals.copy()
- ldict.update(f.f_locals)
+ self.tokens = tokens
- if optimize and lextab:
+ # Validate the tokens
+ def validate_tokens(self):
+ terminals = {}
+ for n in self.tokens:
+ if not _is_identifier.match(n):
+ self.log.error("Bad token name '%s'",n)
+ self.error = 1
+ if n in terminals:
+ self.log.warning("Token '%s' multiply defined", n)
+ terminals[n] = 1
+
+ # Get the literals specifier
+ def get_literals(self):
+ self.literals = self.ldict.get("literals","")
+
+ # Validate literals
+ def validate_literals(self):
try:
- lexobj.readtab(lextab,ldict)
- token = lexobj.token
- input = lexobj.input
- lexer = lexobj
- return lexobj
+ for c in self.literals:
+ if not isinstance(c,StringTypes) or len(c) > 1:
+ self.log.error("Invalid literal %s. Must be a single character", repr(c))
+ self.error = 1
+ continue
- except ImportError:
- pass
+ except TypeError:
+ self.log.error("Invalid literals specification. literals must be a sequence of characters")
+ self.error = 1
+
+ def get_states(self):
+ self.states = self.ldict.get("states",None)
+ # Build statemap
+ if self.states:
+ if not isinstance(self.states,(tuple,list)):
+ self.log.error("states must be defined as a tuple or list")
+ self.error = 1
+ else:
+ for s in self.states:
+ if not isinstance(s,tuple) or len(s) != 2:
+ self.log.error("Invalid state specifier %s. Must be a tuple (statename,'exclusive|inclusive')",repr(s))
+ self.error = 1
+ continue
+ name, statetype = s
+ if not isinstance(name,StringTypes):
+ self.log.error("State name %s must be a string", repr(name))
+ self.error = 1
+ continue
+ if not (statetype == 'inclusive' or statetype == 'exclusive'):
+ self.log.error("State type for state %s must be 'inclusive' or 'exclusive'",name)
+ self.error = 1
+ continue
+ if name in self.stateinfo:
+ self.log.error("State '%s' already defined",name)
+ self.error = 1
+ continue
+ self.stateinfo[name] = statetype
+
+ # Get all of the symbols with a t_ prefix and sort them into various
+ # categories (functions, strings, error functions, and ignore characters)
+
+ def get_rules(self):
+ tsymbols = [f for f in self.ldict if f[:2] == 't_' ]
+
+ # Now build up a list of functions and a list of strings
+
+ self.toknames = { } # Mapping of symbols to token names
+ self.funcsym = { } # Symbols defined as functions
+ self.strsym = { } # Symbols defined as strings
+ self.ignore = { } # Ignore strings by state
+ self.errorf = { } # Error functions by state
+
+ for s in self.stateinfo:
+ self.funcsym[s] = []
+ self.strsym[s] = []
+
+ if len(tsymbols) == 0:
+ self.log.error("No rules of the form t_rulename are defined")
+ self.error = 1
+ return
- # Get the tokens, states, and literals variables (if any)
+ for f in tsymbols:
+ t = self.ldict[f]
+ states, tokname = _statetoken(f,self.stateinfo)
+ self.toknames[f] = tokname
- tokens = ldict.get("tokens",None)
- states = ldict.get("states",None)
- literals = ldict.get("literals","")
+ if hasattr(t,"__call__"):
+ if tokname == 'error':
+ for s in states:
+ self.errorf[s] = t
+ elif tokname == 'ignore':
+ line = func_code(t).co_firstlineno
+ file = func_code(t).co_filename
+ self.log.error("%s:%d: Rule '%s' must be defined as a string",file,line,t.__name__)
+ self.error = 1
+ else:
+ for s in states:
+ self.funcsym[s].append((f,t))
+ elif isinstance(t, StringTypes):
+ if tokname == 'ignore':
+ for s in states:
+ self.ignore[s] = t
+ if "\\" in t:
+ self.log.warning("%s contains a literal backslash '\\'",f)
+
+ elif tokname == 'error':
+ self.log.error("Rule '%s' must be defined as a function", f)
+ self.error = 1
+ else:
+ for s in states:
+ self.strsym[s].append((f,t))
+ else:
+ self.log.error("%s not defined as a function or string", f)
+ self.error = 1
- if not tokens:
- raise SyntaxError,"lex: module does not define 'tokens'"
+ # Sort the functions by line number
+ for f in self.funcsym.values():
+ if sys.version_info[0] < 3:
+ f.sort(lambda x,y: cmp(func_code(x[1]).co_firstlineno,func_code(y[1]).co_firstlineno))
+ else:
+ # Python 3.0
+ f.sort(key=lambda x: func_code(x[1]).co_firstlineno)
- if not (isinstance(tokens,types.ListType) or isinstance(tokens,types.TupleType)):
- raise SyntaxError,"lex: tokens must be a list or tuple."
+ # Sort the strings by regular expression length
+ for s in self.strsym.values():
+ if sys.version_info[0] < 3:
+ s.sort(lambda x,y: (len(x[1]) < len(y[1])) - (len(x[1]) > len(y[1])))
+ else:
+ # Python 3.0
+ s.sort(key=lambda x: len(x[1]),reverse=True)
- # Build a dictionary of valid token names
- lexobj.lextokens = { }
- if not optimize:
- for n in tokens:
- if not _is_identifier.match(n):
- print >>sys.stderr, "lex: Bad token name '%s'" % n
- error = 1
- if warn and lexobj.lextokens.has_key(n):
- print >>sys.stderr, "lex: Warning. Token '%s' multiply defined." % n
- lexobj.lextokens[n] = None
- else:
- for n in tokens: lexobj.lextokens[n] = None
+ # Validate all of the t_rules collected
+ def validate_rules(self):
+ for state in self.stateinfo:
+ # Validate all rules defined by functions
+
+
+
+ for fname, f in self.funcsym[state]:
+ line = func_code(f).co_firstlineno
+ file = func_code(f).co_filename
+ self.files[file] = 1
- if debug:
- print "lex: tokens = '%s'" % lexobj.lextokens.keys()
+ tokname = self.toknames[fname]
+ if isinstance(f, types.MethodType):
+ reqargs = 2
+ else:
+ reqargs = 1
+ nargs = func_code(f).co_argcount
+ if nargs > reqargs:
+ self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,f.__name__)
+ self.error = 1
+ continue
- try:
- for c in literals:
- if not (isinstance(c,types.StringType) or isinstance(c,types.UnicodeType)) or len(c) > 1:
- print >>sys.stderr, "lex: Invalid literal %s. Must be a single character" % repr(c)
- error = 1
+ if nargs < reqargs:
+ self.log.error("%s:%d: Rule '%s' requires an argument", file,line,f.__name__)
+ self.error = 1
continue
- except TypeError:
- print >>sys.stderr, "lex: Invalid literals specification. literals must be a sequence of characters."
- error = 1
-
- lexobj.lexliterals = literals
-
- # Build statemap
- if states:
- if not (isinstance(states,types.TupleType) or isinstance(states,types.ListType)):
- print >>sys.stderr, "lex: states must be defined as a tuple or list."
- error = 1
- else:
- for s in states:
- if not isinstance(s,types.TupleType) or len(s) != 2:
- print >>sys.stderr, "lex: invalid state specifier %s. Must be a tuple (statename,'exclusive|inclusive')" % repr(s)
- error = 1
- continue
- name, statetype = s
- if not isinstance(name,types.StringType):
- print >>sys.stderr, "lex: state name %s must be a string" % repr(name)
- error = 1
- continue
- if not (statetype == 'inclusive' or statetype == 'exclusive'):
- print >>sys.stderr, "lex: state type for state %s must be 'inclusive' or 'exclusive'" % name
- error = 1
- continue
- if stateinfo.has_key(name):
- print >>sys.stderr, "lex: state '%s' already defined." % name
- error = 1
- continue
- stateinfo[name] = statetype
-
- # Get a list of symbols with the t_ or s_ prefix
- tsymbols = [f for f in ldict.keys() if f[:2] == 't_' ]
-
- # Now build up a list of functions and a list of strings
-
- funcsym = { } # Symbols defined as functions
- strsym = { } # Symbols defined as strings
- toknames = { } # Mapping of symbols to token names
-
- for s in stateinfo.keys():
- funcsym[s] = []
- strsym[s] = []
-
- ignore = { } # Ignore strings by state
- errorf = { } # Error functions by state
-
- if len(tsymbols) == 0:
- raise SyntaxError,"lex: no rules of the form t_rulename are defined."
-
- for f in tsymbols:
- t = ldict[f]
- states, tokname = _statetoken(f,stateinfo)
- toknames[f] = tokname
-
- if callable(t):
- for s in states: funcsym[s].append((f,t))
- elif (isinstance(t, types.StringType) or isinstance(t,types.UnicodeType)):
- for s in states: strsym[s].append((f,t))
- else:
- print >>sys.stderr, "lex: %s not defined as a function or string" % f
- error = 1
+ if not f.__doc__:
+ self.log.error("%s:%d: No regular expression defined for rule '%s'",file,line,f.__name__)
+ self.error = 1
+ continue
- # Sort the functions by line number
- for f in funcsym.values():
- f.sort(lambda x,y: cmp(x[1].func_code.co_firstlineno,y[1].func_code.co_firstlineno))
-
- # Sort the strings by regular expression length
- for s in strsym.values():
- s.sort(lambda x,y: (len(x[1]) < len(y[1])) - (len(x[1]) > len(y[1])))
+ try:
+ c = re.compile("(?P<%s>%s)" % (fname,f.__doc__), re.VERBOSE | self.reflags)
+ if c.match(""):
+ self.log.error("%s:%d: Regular expression for rule '%s' matches empty string", file,line,f.__name__)
+ self.error = 1
+ except re.error:
+ _etype, e, _etrace = sys.exc_info()
+ self.log.error("%s:%d: Invalid regular expression for rule '%s'. %s", file,line,f.__name__,e)
+ if '#' in f.__doc__:
+ self.log.error("%s:%d. Make sure '#' in rule '%s' is escaped with '\\#'",file,line, f.__name__)
+ self.error = 1
+
+ # Validate all rules defined by strings
+ for name,r in self.strsym[state]:
+ tokname = self.toknames[name]
+ if tokname == 'error':
+ self.log.error("Rule '%s' must be defined as a function", name)
+ self.error = 1
+ continue
- regexs = { }
+ if not tokname in self.tokens and tokname.find("ignore_") < 0:
+ self.log.error("Rule '%s' defined for an unspecified token %s",name,tokname)
+ self.error = 1
+ continue
- # Build the master regular expressions
- for state in stateinfo.keys():
- regex_list = []
+ try:
+ c = re.compile("(?P<%s>%s)" % (name,r),re.VERBOSE | self.reflags)
+ if (c.match("")):
+ self.log.error("Regular expression for rule '%s' matches empty string",name)
+ self.error = 1
+ except re.error:
+ _etype, e, _etrace = sys.exc_info()
+ self.log.error("Invalid regular expression for rule '%s'. %s",name,e)
+ if '#' in r:
+ self.log.error("Make sure '#' in rule '%s' is escaped with '\\#'",name)
+ self.error = 1
- # Add rules defined by functions first
- for fname, f in funcsym[state]:
- line = f.func_code.co_firstlineno
- file = f.func_code.co_filename
- files[file] = None
- tokname = toknames[fname]
-
- ismethod = isinstance(f, types.MethodType)
-
- if not optimize:
- nargs = f.func_code.co_argcount
- if ismethod:
+ if not self.funcsym[state] and not self.strsym[state]:
+ self.log.error("No rules defined for state '%s'",state)
+ self.error = 1
+
+ # Validate the error function
+ efunc = self.errorf.get(state,None)
+ if efunc:
+ f = efunc
+ line = func_code(f).co_firstlineno
+ file = func_code(f).co_filename
+ self.files[file] = 1
+
+ if isinstance(f, types.MethodType):
reqargs = 2
else:
reqargs = 1
+ nargs = func_code(f).co_argcount
if nargs > reqargs:
- print >>sys.stderr, "%s:%d: Rule '%s' has too many arguments." % (file,line,f.__name__)
- error = 1
- continue
+ self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,f.__name__)
+ self.error = 1
if nargs < reqargs:
- print >>sys.stderr, "%s:%d: Rule '%s' requires an argument." % (file,line,f.__name__)
- error = 1
- continue
+ self.log.error("%s:%d: Rule '%s' requires an argument", file,line,f.__name__)
+ self.error = 1
- if tokname == 'ignore':
- print >>sys.stderr, "%s:%d: Rule '%s' must be defined as a string." % (file,line,f.__name__)
- error = 1
- continue
+ for f in self.files:
+ self.validate_file(f)
- if tokname == 'error':
- errorf[state] = f
- continue
- if f.__doc__:
- if not optimize:
- try:
- c = re.compile("(?P<%s>%s)" % (fname,f.__doc__), re.VERBOSE | reflags)
- if c.match(""):
- print >>sys.stderr, "%s:%d: Regular expression for rule '%s' matches empty string." % (file,line,f.__name__)
- error = 1
- continue
- except re.error,e:
- print >>sys.stderr, "%s:%d: Invalid regular expression for rule '%s'. %s" % (file,line,f.__name__,e)
- if '#' in f.__doc__:
- print >>sys.stderr, "%s:%d. Make sure '#' in rule '%s' is escaped with '\\#'." % (file,line, f.__name__)
- error = 1
- continue
+ # -----------------------------------------------------------------------------
+ # validate_file()
+ #
+ # This checks to see if there are duplicated t_rulename() functions or strings
+ # in the parser input file. This is done using a simple regular expression
+ # match on each line in the given file.
+ # -----------------------------------------------------------------------------
+
+ def validate_file(self,filename):
+ import os.path
+ base,ext = os.path.splitext(filename)
+ if ext != '.py': return # No idea what the file is. Return OK
- if debug:
- print "lex: Adding rule %s -> '%s' (state '%s')" % (f.__name__,f.__doc__, state)
+ try:
+ f = open(filename)
+ lines = f.readlines()
+ f.close()
+ except IOError:
+ return # Couldn't find the file. Don't worry about it
- # Okay. The regular expression seemed okay. Let's append it to the master regular
- # expression we're building
+ fre = re.compile(r'\s*def\s+(t_[a-zA-Z_0-9]*)\(')
+ sre = re.compile(r'\s*(t_[a-zA-Z_0-9]*)\s*=')
- regex_list.append("(?P<%s>%s)" % (fname,f.__doc__))
- else:
- print >>sys.stderr, "%s:%d: No regular expression defined for rule '%s'" % (file,line,f.__name__)
+ counthash = { }
+ linen = 1
+ for l in lines:
+ m = fre.match(l)
+ if not m:
+ m = sre.match(l)
+ if m:
+ name = m.group(1)
+ prev = counthash.get(name)
+ if not prev:
+ counthash[name] = linen
+ else:
+ self.log.error("%s:%d: Rule %s redefined. Previously defined on line %d",filename,linen,name,prev)
+ self.error = 1
+ linen += 1
+
+# -----------------------------------------------------------------------------
+# lex(module)
+#
+# Build all of the regular expression rules from definitions in the supplied module
+# -----------------------------------------------------------------------------
+def lex(module=None,object=None,debug=0,optimize=0,lextab="lextab",reflags=0,nowarn=0,outputdir="", debuglog=None, errorlog=None):
+ global lexer
+ ldict = None
+ stateinfo = { 'INITIAL' : 'inclusive'}
+ lexobj = Lexer()
+ lexobj.lexoptimize = optimize
+ global token,input
- # Now add all of the simple rules
- for name,r in strsym[state]:
- tokname = toknames[name]
+ if errorlog is None:
+ errorlog = PlyLogger(sys.stderr)
+
+ if debug:
+ if debuglog is None:
+ debuglog = PlyLogger(sys.stderr)
- if tokname == 'ignore':
- if "\\" in r:
- print >>sys.stderr, "lex: Warning. %s contains a literal backslash '\\'" % name
- ignore[state] = r
- continue
+ # Get the module dictionary used for the lexer
+ if object: module = object
- if not optimize:
- if tokname == 'error':
- raise SyntaxError,"lex: Rule '%s' must be defined as a function" % name
- error = 1
- continue
+ if module:
+ _items = [(k,getattr(module,k)) for k in dir(module)]
+ ldict = dict(_items)
+ else:
+ ldict = get_caller_module_dict(2)
- if not lexobj.lextokens.has_key(tokname) and tokname.find("ignore_") < 0:
- print >>sys.stderr, "lex: Rule '%s' defined for an unspecified token %s." % (name,tokname)
- error = 1
- continue
- try:
- c = re.compile("(?P<%s>%s)" % (name,r),re.VERBOSE | reflags)
- if (c.match("")):
- print >>sys.stderr, "lex: Regular expression for rule '%s' matches empty string." % name
- error = 1
- continue
- except re.error,e:
- print >>sys.stderr, "lex: Invalid regular expression for rule '%s'. %s" % (name,e)
- if '#' in r:
- print >>sys.stderr, "lex: Make sure '#' in rule '%s' is escaped with '\\#'." % name
+ # Collect parser information from the dictionary
+ linfo = LexerReflect(ldict,log=errorlog,reflags=reflags)
+ linfo.get_all()
+ if not optimize:
+ if linfo.validate_all():
+ raise SyntaxError("Can't build lexer")
- error = 1
- continue
- if debug:
- print "lex: Adding rule %s -> '%s' (state '%s')" % (name,r,state)
+ if optimize and lextab:
+ try:
+ lexobj.readtab(lextab,ldict)
+ token = lexobj.token
+ input = lexobj.input
+ lexer = lexobj
+ return lexobj
- regex_list.append("(?P<%s>%s)" % (name,r))
+ except ImportError:
+ pass
- if not regex_list:
- print >>sys.stderr, "lex: No rules defined for state '%s'" % state
- error = 1
+ # Dump some basic debugging information
+ if debug:
+ debuglog.info("lex: tokens = %r", linfo.tokens)
+ debuglog.info("lex: literals = %r", linfo.literals)
+ debuglog.info("lex: states = %r", linfo.stateinfo)
- regexs[state] = regex_list
+ # Build a dictionary of valid token names
+ lexobj.lextokens = { }
+ for n in linfo.tokens:
+ lexobj.lextokens[n] = 1
+ # Get literals specification
+ if isinstance(linfo.literals,(list,tuple)):
+ lexobj.lexliterals = type(linfo.literals[0])().join(linfo.literals)
+ else:
+ lexobj.lexliterals = linfo.literals
- if not optimize:
- for f in files.keys():
- if not _validate_file(f):
- error = 1
+ # Get the stateinfo dictionary
+ stateinfo = linfo.stateinfo
+
+ regexs = { }
+ # Build the master regular expressions
+ for state in stateinfo:
+ regex_list = []
+
+ # Add rules defined by functions first
+ for fname, f in linfo.funcsym[state]:
+ line = func_code(f).co_firstlineno
+ file = func_code(f).co_filename
+ regex_list.append("(?P<%s>%s)" % (fname,f.__doc__))
+ if debug:
+ debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",fname,f.__doc__, state)
- if error:
- raise SyntaxError,"lex: Unable to build lexer."
+ # Now add all of the simple rules
+ for name,r in linfo.strsym[state]:
+ regex_list.append("(?P<%s>%s)" % (name,r))
+ if debug:
+ debuglog.info("lex: Adding rule %s -> '%s' (state '%s')",name,r, state)
- # From this point forward, we're reasonably confident that we can build the lexer.
- # No more errors will be generated, but there might be some warning messages.
+ regexs[state] = regex_list
# Build the master regular expressions
- for state in regexs.keys():
- lexre, re_text, re_names = _form_master_re(regexs[state],reflags,ldict,toknames)
+ if debug:
+ debuglog.info("lex: ==== MASTER REGEXS FOLLOW ====")
+
+ for state in regexs:
+ lexre, re_text, re_names = _form_master_re(regexs[state],reflags,ldict,linfo.toknames)
lexobj.lexstatere[state] = lexre
lexobj.lexstateretext[state] = re_text
lexobj.lexstaterenames[state] = re_names
if debug:
for i in range(len(re_text)):
- print "lex: state '%s'. regex[%d] = '%s'" % (state, i, re_text[i])
+ debuglog.info("lex: state '%s' : regex[%d] = '%s'",state, i, re_text[i])
- # For inclusive states, we need to add the INITIAL state
- for state,type in stateinfo.items():
- if state != "INITIAL" and type == 'inclusive':
+ # For inclusive states, we need to add the regular expressions from the INITIAL state
+ for state,stype in stateinfo.items():
+ if state != "INITIAL" and stype == 'inclusive':
lexobj.lexstatere[state].extend(lexobj.lexstatere['INITIAL'])
lexobj.lexstateretext[state].extend(lexobj.lexstateretext['INITIAL'])
lexobj.lexstaterenames[state].extend(lexobj.lexstaterenames['INITIAL'])
@@ -806,30 +969,30 @@
lexobj.lexstateinfo = stateinfo
lexobj.lexre = lexobj.lexstatere["INITIAL"]
lexobj.lexretext = lexobj.lexstateretext["INITIAL"]
+ lexobj.lexreflags = reflags
# Set up ignore variables
- lexobj.lexstateignore = ignore
+ lexobj.lexstateignore = linfo.ignore
lexobj.lexignore = lexobj.lexstateignore.get("INITIAL","")
# Set up error functions
- lexobj.lexstateerrorf = errorf
- lexobj.lexerrorf = errorf.get("INITIAL",None)
- if warn and not lexobj.lexerrorf:
- print >>sys.stderr, "lex: Warning. no t_error rule is defined."
+ lexobj.lexstateerrorf = linfo.errorf
+ lexobj.lexerrorf = linfo.errorf.get("INITIAL",None)
+ if not lexobj.lexerrorf:
+ errorlog.warning("No t_error rule is defined")
# Check state information for ignore and error rules
for s,stype in stateinfo.items():
if stype == 'exclusive':
- if warn and not errorf.has_key(s):
- print >>sys.stderr, "lex: Warning. no error rule is defined for exclusive state '%s'" % s
- if warn and not ignore.has_key(s) and lexobj.lexignore:
- print >>sys.stderr, "lex: Warning. no ignore rule is defined for exclusive state '%s'" % s
+ if not s in linfo.errorf:
+ errorlog.warning("No error rule is defined for exclusive state '%s'", s)
+ if not s in linfo.ignore and lexobj.lexignore:
+ errorlog.warning("No ignore rule is defined for exclusive state '%s'", s)
elif stype == 'inclusive':
- if not errorf.has_key(s):
- errorf[s] = errorf.get("INITIAL",None)
- if not ignore.has_key(s):
- ignore[s] = ignore.get("INITIAL","")
-
+ if not s in linfo.errorf:
+ linfo.errorf[s] = linfo.errorf.get("INITIAL",None)
+ if not s in linfo.ignore:
+ linfo.ignore[s] = linfo.ignore.get("INITIAL","")
# Create global versions of the token() and input() functions
token = lexobj.token
@@ -856,7 +1019,7 @@
data = f.read()
f.close()
except IndexError:
- print "Reading from standard input (type EOF to end):"
+ sys.stdout.write("Reading from standard input (type EOF to end):\n")
data = sys.stdin.read()
if lexer:
@@ -872,8 +1035,7 @@
while 1:
tok = _token()
if not tok: break
- print "(%s,%r,%d,%d)" % (tok.type, tok.value, tok.lineno,tok.lexpos)
-
+ sys.stdout.write("(%s,%r,%d,%d)\n" % (tok.type, tok.value, tok.lineno,tok.lexpos))
# -----------------------------------------------------------------------------
# @TOKEN(regex)
@@ -884,7 +1046,7 @@
def TOKEN(r):
def set_doc(f):
- if callable(r):
+ if hasattr(r,"__call__"):
f.__doc__ = r.__doc__
else:
f.__doc__ = r
diff -ruN ply.orig/yacc.py ply/yacc.py
--- other-licenses/ply/ply.orig/yacc.py 2010-04-02 19:02:56.000000000 +0300
+++ other-licenses/ply/ply/yacc.py 2009-09-02 17:27:23.000000000 +0300
@@ -1,26 +1,35 @@
-#-----------------------------------------------------------------------------
+# -----------------------------------------------------------------------------
# ply: yacc.py
#
-# Author(s): David M. Beazley (dave@dabeaz.com)
-#
-# Copyright (C) 2001-2008, David M. Beazley
-#
-# This library is free software; you can redistribute it and/or
-# modify it under the terms of the GNU Lesser General Public
-# License as published by the Free Software Foundation; either
-# version 2.1 of the License, or (at your option) any later version.
-#
-# This library is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-# Lesser General Public License for more details.
-#
-# You should have received a copy of the GNU Lesser General Public
-# License along with this library; if not, write to the Free Software
-# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-#
-# See the file COPYING for a complete copy of the LGPL.
-#
+# Copyright (C) 2001-2009,
+# David M. Beazley (Dabeaz LLC)
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+# * Redistributions of source code must retain the above copyright notice,
+# this list of conditions and the following disclaimer.
+# * Redistributions in binary form must reproduce the above copyright notice,
+# this list of conditions and the following disclaimer in the documentation
+# and/or other materials provided with the distribution.
+# * Neither the name of the David Beazley or Dabeaz LLC may be used to
+# endorse or promote products derived from this software without
+# specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+# -----------------------------------------------------------------------------
#
# This implements an LR parser that is constructed from grammar rules defined
# as Python functions. The grammer is specified by supplying the BNF inside
@@ -50,8 +59,8 @@
# own risk!
# ----------------------------------------------------------------------------
-__version__ = "2.5"
-__tabversion__ = "2.4" # Table version
+__version__ = "3.3"
+__tabversion__ = "3.2" # Table version
#-----------------------------------------------------------------------------
# === User configurable parameters ===
@@ -71,24 +80,83 @@
yaccdevel = 0 # Set to True if developing yacc. This turns off optimized
# implementations of certain functions.
-import re, types, sys, cStringIO, md5, os.path
+resultlimit = 40 # Size limit of results when running in debug mode.
-# Exception raised for yacc-related errors
-class YaccError(Exception): pass
+pickle_protocol = 0 # Protocol to use when writing pickle files
-# Exception raised for errors raised in production rules
-class SyntaxError(Exception): pass
+import re, types, sys, os.path
+# Compatibility function for python 2.6/3.0
+if sys.version_info[0] < 3:
+ def func_code(f):
+ return f.func_code
+else:
+ def func_code(f):
+ return f.__code__
-# Available instance types. This is used when parsers are defined by a class.
-# it's a little funky because I want to preserve backwards compatibility
-# with Python 2.0 where types.ObjectType is undefined.
-
+# Compatibility
try:
- _INSTANCETYPE = (types.InstanceType, types.ObjectType)
+ MAXINT = sys.maxint
except AttributeError:
- _INSTANCETYPE = types.InstanceType
- class object: pass # Note: needed if no new-style classes present
+ MAXINT = sys.maxsize
+
+# Python 2.x/3.0 compatibility.
+def load_ply_lex():
+ if sys.version_info[0] < 3:
+ import lex
+ else:
+ import ply.lex as lex
+ return lex
+
+# This object is a stand-in for a logging object created by the
+# logging module. PLY will use this by default to create things
+# such as the parser.out file. If a user wants more detailed
+# information, they can create their own logging object and pass
+# it into PLY.
+
+class PlyLogger(object):
+ def __init__(self,f):
+ self.f = f
+ def debug(self,msg,*args,**kwargs):
+ self.f.write((msg % args) + "\n")
+ info = debug
+
+ def warning(self,msg,*args,**kwargs):
+ self.f.write("WARNING: "+ (msg % args) + "\n")
+
+ def error(self,msg,*args,**kwargs):
+ self.f.write("ERROR: " + (msg % args) + "\n")
+
+ critical = debug
+
+# Null logger is used when no output is generated. Does nothing.
+class NullLogger(object):
+ def __getattribute__(self,name):
+ return self
+ def __call__(self,*args,**kwargs):
+ return self
+
+# Exception raised for yacc-related errors
+class YaccError(Exception): pass
+
+# Format the result message that the parser produces when running in debug mode.
+def format_result(r):
+ repr_str = repr(r)
+ if '\n' in repr_str: repr_str = repr(repr_str)
+ if len(repr_str) > resultlimit:
+ repr_str = repr_str[:resultlimit]+" ..."
+ result = "<%s @ 0x%x> (%s)" % (type(r).__name__,id(r),repr_str)
+ return result
+
+
+# Format stack entries when the parser is running in debug mode
+def format_stack_entry(r):
+ repr_str = repr(r)
+ if '\n' in repr_str: repr_str = repr(repr_str)
+ if len(repr_str) < 16:
+ return repr_str
+ else:
+ return "<%s @ 0x%x>" % (type(r).__name__,id(r))
#-----------------------------------------------------------------------------
# === LR Parsing Engine ===
@@ -142,6 +210,9 @@
def lineno(self,n):
return getattr(self.slice[n],"lineno",0)
+ def set_lineno(self,n,lineno):
+ self.slice[n].lineno = lineno
+
def linespan(self,n):
startline = getattr(self.slice[n],"lineno",0)
endline = getattr(self.slice[n],"endlineno",startline)
@@ -159,27 +230,18 @@
raise SyntaxError
-# The LR Parsing engine. This is defined as a class so that multiple parsers
-# can exist in the same process. A user never instantiates this directly.
-# Instead, the global yacc() function should be used to create a suitable Parser
-# object.
-
-class Parser:
- def __init__(self,magic=None):
-
- # This is a hack to keep users from trying to instantiate a Parser
- # object directly.
-
- if magic != "xyzzy":
- raise YaccError, "Can't directly instantiate Parser. Use yacc() instead."
-
- # Reset internal state
- self.productions = None # List of productions
- self.errorfunc = None # Error handling function
- self.action = { } # LR Action table
- self.goto = { } # LR goto table
- self.require = { } # Attribute require table
- self.method = "Unknown LR" # Table construction method used
+# -----------------------------------------------------------------------------
+# == LRParser ==
+#
+# The LR Parsing engine.
+# -----------------------------------------------------------------------------
+
+class LRParser:
+ def __init__(self,lrtab,errorf):
+ self.productions = lrtab.lr_productions
+ self.action = lrtab.lr_action
+ self.goto = lrtab.lr_goto
+ self.errorfunc = errorf
def errok(self):
self.errorok = 1
@@ -194,6 +256,8 @@
def parse(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None):
if debug or yaccdevel:
+ if isinstance(debug,int):
+ debug = PlyLogger(sys.stderr)
return self.parsedebug(input,lexer,debug,tracking,tokenfunc)
elif tracking:
return self.parseopt(input,lexer,debug,tracking,tokenfunc)
@@ -215,7 +279,7 @@
#
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
- def parsedebug(self,input=None,lexer=None,debug=0,tracking=0,tokenfunc=None):
+ def parsedebug(self,input=None,lexer=None,debug=None,tracking=0,tokenfunc=None):
lookahead = None # Current lookahead symbol
lookaheadstack = [ ] # Stack of lookahead symbols
actions = self.action # Local reference to action table (to avoid lookup on self.)
@@ -223,12 +287,16 @@
prod = self.productions # Local reference to production list (to avoid lookup on self.)
pslice = YaccProduction(None) # Production object passed to grammar rules
errorcount = 0 # Used during error recovery
- endsym = "$end" # End symbol
+
+ # --! DEBUG
+ debug.info("PLY: PARSE DEBUG START")
+ # --! DEBUG
+
# If no lexer was given, we will try to use the lex module
if not lexer:
- import lex
+ lex = load_ply_lex()
lexer = lex.lexer
-
+
# Set up the lexer and parser objects on pslice
pslice.lexer = lexer
pslice.parser = self
@@ -257,7 +325,7 @@
statestack.append(0)
sym = YaccSymbol()
- sym.type = endsym
+ sym.type = "$end"
symstack.append(sym)
state = 0
while 1:
@@ -266,8 +334,8 @@
# the next token off of the lookaheadstack or from the lexer
# --! DEBUG
- if debug > 1:
- print 'state', state
+ debug.debug('')
+ debug.debug('State : %s', state)
# --! DEBUG
if not lookahead:
@@ -277,35 +345,25 @@
lookahead = lookaheadstack.pop()
if not lookahead:
lookahead = YaccSymbol()
- lookahead.type = endsym
+ lookahead.type = "$end"
# --! DEBUG
- if debug:
- errorlead = ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip()
+ debug.debug('Stack : %s',
+ ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip())
# --! DEBUG
# Check the action table
ltype = lookahead.type
t = actions[state].get(ltype)
- # --! DEBUG
- if debug > 1:
- print 'action', t
- # --! DEBUG
-
if t is not None:
if t > 0:
# shift a symbol on the stack
- if ltype is endsym:
- # Error, end of input
- sys.stderr.write("yacc: Parse error. EOF\n")
- return
statestack.append(t)
state = t
# --! DEBUG
- if debug > 1:
- sys.stderr.write("%-60s shift state %s\n" % (errorlead, t))
+ debug.debug("Action : Shift and goto state %s", t)
# --! DEBUG
symstack.append(lookahead)
@@ -327,8 +385,11 @@
sym.value = None
# --! DEBUG
- if debug > 1:
- sys.stderr.write("%-60s reduce %d\n" % (errorlead, -t))
+ if plen:
+ debug.info("Action : Reduce rule [%s] with %s and goto state %d", p.str, "["+",".join([format_stack_entry(_v.value) for _v in symstack[-plen:]])+"]",-t)
+ else:
+ debug.info("Action : Reduce rule [%s] with %s and goto state %d", p.str, [],-t)
+
# --! DEBUG
if plen:
@@ -355,9 +416,12 @@
try:
# Call the grammar rule with our special slice object
- p.func(pslice)
del symstack[-plen:]
del statestack[-plen:]
+ p.callable(pslice)
+ # --! DEBUG
+ debug.info("Result : %s", format_result(pslice[0]))
+ # --! DEBUG
symstack.append(sym)
state = goto[statestack[-1]][pname]
statestack.append(state)
@@ -393,7 +457,10 @@
try:
# Call the grammar rule with our special slice object
- p.func(pslice)
+ p.callable(pslice)
+ # --! DEBUG
+ debug.info("Result : %s", format_result(pslice[0]))
+ # --! DEBUG
symstack.append(sym)
state = goto[statestack[-1]][pname]
statestack.append(state)
@@ -412,13 +479,18 @@
if t == 0:
n = symstack[-1]
- return getattr(n,"value",None)
+ result = getattr(n,"value",None)
+ # --! DEBUG
+ debug.info("Done : Returning %s", format_result(result))
+ debug.info("PLY: PARSE DEBUG END")
+ # --! DEBUG
+ return result
if t == None:
# --! DEBUG
- if debug:
- sys.stderr.write(errorlead + "\n")
+ debug.error('Error : %s',
+ ("%s . %s" % (" ".join([xx.type for xx in symstack][1:]), str(lookahead))).lstrip())
# --! DEBUG
# We have some kind of parsing error here. To handle
@@ -435,13 +507,15 @@
errorcount = error_count
self.errorok = 0
errtoken = lookahead
- if errtoken.type is endsym:
+ if errtoken.type == "$end":
errtoken = None # End of file!
if self.errorfunc:
global errok,token,restart
errok = self.errok # Set some special functions available in error recovery
token = get_token
restart = self.restart
+ if errtoken and not hasattr(errtoken,'lexer'):
+ errtoken.lexer = lexer
tok = self.errorfunc(errtoken)
del errok, token, restart # Delete special functions
@@ -471,7 +545,7 @@
# entire parse has been rolled back and we're completely hosed. The token is
# discarded and we just keep going.
- if len(statestack) <= 1 and lookahead.type is not endsym:
+ if len(statestack) <= 1 and lookahead.type != "$end":
lookahead = None
errtoken = None
state = 0
@@ -483,7 +557,7 @@
# at the end of the file. nuke the top entry and generate an error token
# Start nuking entries on the stack
- if lookahead.type is endsym:
+ if lookahead.type == "$end":
# Whoa. We're really hosed here. Bail out
return
@@ -509,7 +583,7 @@
continue
# Call an error function here
- raise RuntimeError, "yacc: internal parser error!!!\n"
+ raise RuntimeError("yacc: internal parser error!!!\n")
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# parseopt().
@@ -531,7 +605,7 @@
# If no lexer was given, we will try to use the lex module
if not lexer:
- import lex
+ lex = load_ply_lex()
lexer = lex.lexer
# Set up the lexer and parser objects on pslice
@@ -586,10 +660,6 @@
if t is not None:
if t > 0:
# shift a symbol on the stack
- if ltype == '$end':
- # Error, end of input
- sys.stderr.write("yacc: Parse error. EOF\n")
- return
statestack.append(t)
state = t
@@ -635,9 +705,9 @@
try:
# Call the grammar rule with our special slice object
- p.func(pslice)
del symstack[-plen:]
del statestack[-plen:]
+ p.callable(pslice)
symstack.append(sym)
state = goto[statestack[-1]][pname]
statestack.append(state)
@@ -673,7 +743,7 @@
try:
# Call the grammar rule with our special slice object
- p.func(pslice)
+ p.callable(pslice)
symstack.append(sym)
state = goto[statestack[-1]][pname]
statestack.append(state)
@@ -717,6 +787,8 @@
errok = self.errok # Set some special functions available in error recovery
token = get_token
restart = self.restart
+ if errtoken and not hasattr(errtoken,'lexer'):
+ errtoken.lexer = lexer
tok = self.errorfunc(errtoken)
del errok, token, restart # Delete special functions
@@ -784,7 +856,7 @@
continue
# Call an error function here
- raise RuntimeError, "yacc: internal parser error!!!\n"
+ raise RuntimeError("yacc: internal parser error!!!\n")
# !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
# parseopt_notrack().
@@ -805,7 +877,7 @@
# If no lexer was given, we will try to use the lex module
if not lexer:
- import lex
+ lex = load_ply_lex()
lexer = lex.lexer
# Set up the lexer and parser objects on pslice
@@ -860,10 +932,6 @@
if t is not None:
if t > 0:
# shift a symbol on the stack
- if ltype == '$end':
- # Error, end of input
- sys.stderr.write("yacc: Parse error. EOF\n")
- return
statestack.append(t)
state = t
@@ -898,9 +966,9 @@
try:
# Call the grammar rule with our special slice object
- p.func(pslice)
del symstack[-plen:]
del statestack[-plen:]
+ p.callable(pslice)
symstack.append(sym)
state = goto[statestack[-1]][pname]
statestack.append(state)
@@ -930,7 +998,7 @@
try:
# Call the grammar rule with our special slice object
- p.func(pslice)
+ p.callable(pslice)
symstack.append(sym)
state = goto[statestack[-1]][pname]
statestack.append(state)
@@ -974,6 +1042,8 @@
errok = self.errok # Set some special functions available in error recovery
token = get_token
restart = self.restart
+ if errtoken and not hasattr(errtoken,'lexer'):
+ errtoken.lexer = lexer
tok = self.errorfunc(errtoken)
del errok, token, restart # Delete special functions
@@ -1041,169 +1111,172 @@
continue
# Call an error function here
- raise RuntimeError, "yacc: internal parser error!!!\n"
-
+ raise RuntimeError("yacc: internal parser error!!!\n")
# -----------------------------------------------------------------------------
-# === Parser Construction ===
+# === Grammar Representation ===
#
-# The following functions and variables are used to implement the yacc() function
-# itself. This is pretty hairy stuff involving lots of error checking,
-# construction of LR items, kernels, and so forth. Although a lot of
-# this work is done using global variables, the resulting Parser object
-# is completely self contained--meaning that it is safe to repeatedly
-# call yacc() with different grammars in the same application.
+# The following functions, classes, and variables are used to represent and
+# manipulate the rules that make up a grammar.
# -----------------------------------------------------------------------------
-# -----------------------------------------------------------------------------
-# validate_file()
-#
-# This function checks to see if there are duplicated p_rulename() functions
-# in the parser module file. Without this function, it is really easy for
-# users to make mistakes by cutting and pasting code fragments (and it's a real
-# bugger to try and figure out why the resulting parser doesn't work). Therefore,
-# we just do a little regular expression pattern matching of def statements
-# to try and detect duplicates.
-# -----------------------------------------------------------------------------
-
-def validate_file(filename):
- base,ext = os.path.splitext(filename)
- if ext != '.py': return 1 # No idea. Assume it's okay.
+import re
- try:
- f = open(filename)
- lines = f.readlines()
- f.close()
- except IOError:
- return 1 # Oh well
-
- # Match def p_funcname(
- fre = re.compile(r'\s*def\s+(p_[a-zA-Z_0-9]*)\(')
- counthash = { }
- linen = 1
- noerror = 1
- for l in lines:
- m = fre.match(l)
- if m:
- name = m.group(1)
- prev = counthash.get(name)
- if not prev:
- counthash[name] = linen
- else:
- sys.stderr.write("%s:%d: Function %s redefined. Previously defined on line %d\n" % (filename,linen,name,prev))
- noerror = 0
- linen += 1
- return noerror
-
-# This function looks for functions that might be grammar rules, but which don't have the proper p_suffix.
-def validate_dict(d):
- for n,v in d.items():
- if n[0:2] == 'p_' and type(v) in (types.FunctionType, types.MethodType): continue
- if n[0:2] == 't_': continue
-
- if n[0:2] == 'p_':
- sys.stderr.write("yacc: Warning. '%s' not defined as a function\n" % n)
- if 1 and isinstance(v,types.FunctionType) and v.func_code.co_argcount == 1:
- try:
- doc = v.__doc__.split(" ")
- if doc[1] == ':':
- sys.stderr.write("%s:%d: Warning. Possible grammar rule '%s' defined without p_ prefix.\n" % (v.func_code.co_filename, v.func_code.co_firstlineno,n))
- except StandardError:
- pass
+# regex matching identifiers
+_is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$')
# -----------------------------------------------------------------------------
-# === GRAMMAR FUNCTIONS ===
+# class Production:
#
-# The following global variables and functions are used to store, manipulate,
-# and verify the grammar rules specified by the user.
-# -----------------------------------------------------------------------------
-
-# Initialize all of the global variables used during grammar construction
-def initialize_vars():
- global Productions, Prodnames, Prodmap, Terminals
- global Nonterminals, First, Follow, Precedence, UsedPrecedence, LRitems
- global Errorfunc, Signature, Requires
-
- Productions = [None] # A list of all of the productions. The first
- # entry is always reserved for the purpose of
- # building an augmented grammar
-
- Prodnames = { } # A dictionary mapping the names of nonterminals to a list of all
- # productions of that nonterminal.
+# This class stores the raw information about a single production or grammar rule.
+# A grammar rule refers to a specification such as this:
+#
+# expr : expr PLUS term
+#
+# Here are the basic attributes defined on all productions
+#
+# name - Name of the production. For example 'expr'
+# prod - A list of symbols on the right side ['expr','PLUS','term']
+# prec - Production precedence level
+# number - Production number.
+# func - Function that executes on reduce
+# file - File where production function is defined
+# lineno - Line number where production function is defined
+#
+# The following attributes are defined or optional.
+#
+# len - Length of the production (number of symbols on right hand side)
+# usyms - Set of unique symbols found in the production
+# -----------------------------------------------------------------------------
+
+class Production(object):
+ reduced = 0
+ def __init__(self,number,name,prod,precedence=('right',0),func=None,file='',line=0):
+ self.name = name
+ self.prod = tuple(prod)
+ self.number = number
+ self.func = func
+ self.callable = None
+ self.file = file
+ self.line = line
+ self.prec = precedence
- Prodmap = { } # A dictionary that is only used to detect duplicate
- # productions.
+ # Internal settings used during table construction
+
+ self.len = len(self.prod) # Length of the production
- Terminals = { } # A dictionary mapping the names of terminal symbols to a
- # list of the rules where they are used.
+ # Create a list of unique production symbols used in the production
+ self.usyms = [ ]
+ for s in self.prod:
+ if s not in self.usyms:
+ self.usyms.append(s)
+
+ # List of all LR items for the production
+ self.lr_items = []
+ self.lr_next = None
- Nonterminals = { } # A dictionary mapping names of nonterminals to a list
- # of rule numbers where they are used.
+ # Create a string representation
+ if self.prod:
+ self.str = "%s -> %s" % (self.name," ".join(self.prod))
+ else:
+ self.str = "%s -> <empty>" % self.name
- First = { } # A dictionary of precomputed FIRST(x) symbols
+ def __str__(self):
+ return self.str
- Follow = { } # A dictionary of precomputed FOLLOW(x) symbols
+ def __repr__(self):
+ return "Production("+str(self)+")"
- Precedence = { } # Precedence rules for each terminal. Contains tuples of the
- # form ('right',level) or ('nonassoc', level) or ('left',level)
+ def __len__(self):
+ return len(self.prod)
- UsedPrecedence = { } # Precedence rules that were actually used by the grammer.
- # This is only used to provide error checking and to generate
- # a warning about unused precedence rules.
+ def __nonzero__(self):
+ return 1
- LRitems = [ ] # A list of all LR items for the grammar. These are the
- # productions with the "dot" like E -> E . PLUS E
+ def __getitem__(self,index):
+ return self.prod[index]
+
+ # Return the nth lr_item from the production (or None if at the end)
+ def lr_item(self,n):
+ if n > len(self.prod): return None
+ p = LRItem(self,n)
- Errorfunc = None # User defined error handler
+ # Precompute the list of productions immediately following. Hack. Remove later
+ try:
+ p.lr_after = Prodnames[p.prod[n+1]]
+ except (IndexError,KeyError):
+ p.lr_after = []
+ try:
+ p.lr_before = p.prod[n-1]
+ except IndexError:
+ p.lr_before = None
- Signature = md5.new() # Digital signature of the grammar rules, precedence
- # and other information. Used to determined when a
- # parsing table needs to be regenerated.
+ return p
- Signature.update(__tabversion__)
+ # Bind the production function name to a callable
+ def bind(self,pdict):
+ if self.func:
+ self.callable = pdict[self.func]
+
+# This class serves as a minimal standin for Production objects when
+# reading table data from files. It only contains information
+# actually used by the LR parsing engine, plus some additional
+# debugging information.
+class MiniProduction(object):
+ def __init__(self,str,name,len,func,file,line):
+ self.name = name
+ self.len = len
+ self.func = func
+ self.callable = None
+ self.file = file
+ self.line = line
+ self.str = str
+ def __str__(self):
+ return self.str
+ def __repr__(self):
+ return "MiniProduction(%s)" % self.str
- Requires = { } # Requires list
+ # Bind the production function name to a callable
+ def bind(self,pdict):
+ if self.func:
+ self.callable = pdict[self.func]
- # File objects used when creating the parser.out debugging file
- global _vf, _vfc
- _vf = cStringIO.StringIO()
- _vfc = cStringIO.StringIO()
# -----------------------------------------------------------------------------
-# class Production:
+# class LRItem
#
-# This class stores the raw information about a single production or grammar rule.
-# It has a few required attributes:
+# This class represents a specific stage of parsing a production rule. For
+# example:
#
-# name - Name of the production (nonterminal)
-# prod - A list of symbols making up its production
-# number - Production number.
+# expr : expr . PLUS term
#
-# In addition, a few additional attributes are used to help with debugging or
-# optimization of table generation.
+# In the above, the "." represents the current location of the parse. Here
+# basic attributes:
#
-# file - File where production action is defined.
-# lineno - Line number where action is defined
-# func - Action function
-# prec - Precedence level
-# lr_next - Next LR item. Example, if we are ' E -> E . PLUS E'
-# then lr_next refers to 'E -> E PLUS . E'
-# lr_index - LR item index (location of the ".") in the prod list.
+# name - Name of the production. For example 'expr'
+# prod - A list of symbols on the right side ['expr','.', 'PLUS','term']
+# number - Production number.
+#
+# lr_next Next LR item. Example, if we are ' expr -> expr . PLUS term'
+# then lr_next refers to 'expr -> expr PLUS . term'
+# lr_index - LR item index (location of the ".") in the prod list.
# lookaheads - LALR lookahead symbols for this item
-# len - Length of the production (number of symbols on right hand side)
+# len - Length of the production (number of symbols on right hand side)
+# lr_after - List of all productions that immediately follow
+# lr_before - Grammar symbol immediately before
# -----------------------------------------------------------------------------
-class Production:
- def __init__(self,**kw):
- for k,v in kw.items():
- setattr(self,k,v)
- self.lr_index = -1
- self.lr0_added = 0 # Flag indicating whether or not added to LR0 closure
- self.lr1_added = 0 # Flag indicating whether or not added to LR1
- self.usyms = [ ]
+class LRItem(object):
+ def __init__(self,p,n):
+ self.name = p.name
+ self.prod = list(p.prod)
+ self.number = p.number
+ self.lr_index = n
self.lookaheads = { }
- self.lk_added = { }
- self.setnumbers = [ ]
+ self.prod.insert(n,".")
+ self.prod = tuple(self.prod)
+ self.len = len(self.prod)
+ self.usyms = p.usyms
def __str__(self):
if self.prod:
@@ -1213,932 +1286,597 @@
return s
def __repr__(self):
- return str(self)
-
- # Compute lr_items from the production
- def lr_item(self,n):
- if n > len(self.prod): return None
- p = Production()
- p.name = self.name
- p.prod = list(self.prod)
- p.number = self.number
- p.lr_index = n
- p.lookaheads = { }
- p.setnumbers = self.setnumbers
- p.prod.insert(n,".")
- p.prod = tuple(p.prod)
- p.len = len(p.prod)
- p.usyms = self.usyms
-
- # Precompute list of productions immediately following
- try:
- p.lrafter = Prodnames[p.prod[n+1]]
- except (IndexError,KeyError),e:
- p.lrafter = []
- try:
- p.lrbefore = p.prod[n-1]
- except IndexError:
- p.lrbefore = None
-
- return p
-
-class MiniProduction:
- pass
+ return "LRItem("+str(self)+")"
-# regex matching identifiers
-_is_identifier = re.compile(r'^[a-zA-Z0-9_-]+$')
+# -----------------------------------------------------------------------------
+# rightmost_terminal()
+#
+# Return the rightmost terminal from a list of symbols. Used in add_production()
+# -----------------------------------------------------------------------------
+def rightmost_terminal(symbols, terminals):
+ i = len(symbols) - 1
+ while i >= 0:
+ if symbols[i] in terminals:
+ return symbols[i]
+ i -= 1
+ return None
# -----------------------------------------------------------------------------
-# add_production()
+# === GRAMMAR CLASS ===
#
-# Given an action function, this function assembles a production rule.
-# The production rule is assumed to be found in the function's docstring.
-# This rule has the general syntax:
-#
-# name1 ::= production1
-# | production2
-# | production3
-# ...
-# | productionn
-# name2 ::= production1
-# | production2
-# ...
-# -----------------------------------------------------------------------------
-
-def add_production(f,file,line,prodname,syms):
-
- if Terminals.has_key(prodname):
- sys.stderr.write("%s:%d: Illegal rule name '%s'. Already defined as a token.\n" % (file,line,prodname))
- return -1
- if prodname == 'error':
- sys.stderr.write("%s:%d: Illegal rule name '%s'. error is a reserved word.\n" % (file,line,prodname))
- return -1
-
- if not _is_identifier.match(prodname):
- sys.stderr.write("%s:%d: Illegal rule name '%s'\n" % (file,line,prodname))
- return -1
-
- for x in range(len(syms)):
- s = syms[x]
- if s[0] in "'\"":
- try:
- c = eval(s)
- if (len(c) > 1):
- sys.stderr.write("%s:%d: Literal token %s in rule '%s' may only be a single character\n" % (file,line,s, prodname))
- return -1
- if not Terminals.has_key(c):
- Terminals[c] = []
- syms[x] = c
- continue
- except SyntaxError:
- pass
- if not _is_identifier.match(s) and s != '%prec':
- sys.stderr.write("%s:%d: Illegal name '%s' in rule '%s'\n" % (file,line,s, prodname))
- return -1
-
- # See if the rule is already in the rulemap
- map = "%s -> %s" % (prodname,syms)
- if Prodmap.has_key(map):
- m = Prodmap[map]
- sys.stderr.write("%s:%d: Duplicate rule %s.\n" % (file,line, m))
- sys.stderr.write("%s:%d: Previous definition at %s:%d\n" % (file,line, m.file, m.line))
- return -1
-
- p = Production()
- p.name = prodname
- p.prod = syms
- p.file = file
- p.line = line
- p.func = f
- p.number = len(Productions)
-
-
- Productions.append(p)
- Prodmap[map] = p
- if not Nonterminals.has_key(prodname):
- Nonterminals[prodname] = [ ]
-
- # Add all terminals to Terminals
- i = 0
- while i < len(p.prod):
- t = p.prod[i]
- if t == '%prec':
- try:
- precname = p.prod[i+1]
- except IndexError:
- sys.stderr.write("%s:%d: Syntax error. Nothing follows %%prec.\n" % (p.file,p.line))
- return -1
-
- prec = Precedence.get(precname,None)
- if not prec:
- sys.stderr.write("%s:%d: Nothing known about the precedence of '%s'\n" % (p.file,p.line,precname))
- return -1
- else:
- p.prec = prec
- UsedPrecedence[precname] = 1
- del p.prod[i]
- del p.prod[i]
- continue
-
- if Terminals.has_key(t):
- Terminals[t].append(p.number)
- # Is a terminal. We'll assign a precedence to p based on this
- if not hasattr(p,"prec"):
- p.prec = Precedence.get(t,('right',0))
- else:
- if not Nonterminals.has_key(t):
- Nonterminals[t] = [ ]
- Nonterminals[t].append(p.number)
- i += 1
-
- if not hasattr(p,"prec"):
- p.prec = ('right',0)
-
- # Set final length of productions
- p.len = len(p.prod)
- p.prod = tuple(p.prod)
-
- # Calculate unique syms in the production
- p.usyms = [ ]
- for s in p.prod:
- if s not in p.usyms:
- p.usyms.append(s)
+# The following class represents the contents of the specified grammar along
+# with various computed properties such as first sets, follow sets, LR items, etc.
+# This data is used for critical parts of the table generation process later.
+# -----------------------------------------------------------------------------
- # Add to the global productions list
- try:
- Prodnames[p.name].append(p)
- except KeyError:
- Prodnames[p.name] = [ p ]
- return 0
-
-# Given a raw rule function, this function rips out its doc string
-# and adds rules to the grammar
-
-def add_function(f):
- line = f.func_code.co_firstlineno
- file = f.func_code.co_filename
- error = 0
+class GrammarError(YaccError): pass
- if isinstance(f,types.MethodType):
- reqdargs = 2
- else:
- reqdargs = 1
+class Grammar(object):
+ def __init__(self,terminals):
+ self.Productions = [None] # A list of all of the productions. The first
+ # entry is always reserved for the purpose of
+ # building an augmented grammar
- if f.func_code.co_argcount > reqdargs:
- sys.stderr.write("%s:%d: Rule '%s' has too many arguments.\n" % (file,line,f.__name__))
- return -1
-
- if f.func_code.co_argcount < reqdargs:
- sys.stderr.write("%s:%d: Rule '%s' requires an argument.\n" % (file,line,f.__name__))
- return -1
-
- if f.__doc__:
- # Split the doc string into lines
- pstrings = f.__doc__.splitlines()
- lastp = None
- dline = line
- for ps in pstrings:
- dline += 1
- p = ps.split()
- if not p: continue
- try:
- if p[0] == '|':
- # This is a continuation of a previous rule
- if not lastp:
- sys.stderr.write("%s:%d: Misplaced '|'.\n" % (file,dline))
- return -1
- prodname = lastp
- if len(p) > 1:
- syms = p[1:]
- else:
- syms = [ ]
- else:
- prodname = p[0]
- lastp = prodname
- assign = p[1]
- if len(p) > 2:
- syms = p[2:]
- else:
- syms = [ ]
- if assign != ':' and assign != '::=':
- sys.stderr.write("%s:%d: Syntax error. Expected ':'\n" % (file,dline))
- return -1
+ self.Prodnames = { } # A dictionary mapping the names of nonterminals to a list of all
+ # productions of that nonterminal.
+ self.Prodmap = { } # A dictionary that is only used to detect duplicate
+ # productions.
- e = add_production(f,file,dline,prodname,syms)
- error += e
+ self.Terminals = { } # A dictionary mapping the names of terminal symbols to a
+ # list of the rules where they are used.
+ for term in terminals:
+ self.Terminals[term] = []
- except StandardError:
- sys.stderr.write("%s:%d: Syntax error in rule '%s'\n" % (file,dline,ps))
- error -= 1
- else:
- sys.stderr.write("%s:%d: No documentation string specified in function '%s'\n" % (file,line,f.__name__))
- return error
+ self.Terminals['error'] = []
+ self.Nonterminals = { } # A dictionary mapping names of nonterminals to a list
+ # of rule numbers where they are used.
-# Cycle checking code (Michael Dyck)
+ self.First = { } # A dictionary of precomputed FIRST(x) symbols
-def compute_reachable():
- '''
- Find each symbol that can be reached from the start symbol.
- Print a warning for any nonterminals that can't be reached.
- (Unused terminals have already had their warning.)
- '''
- Reachable = { }
- for s in Terminals.keys() + Nonterminals.keys():
- Reachable[s] = 0
-
- mark_reachable_from( Productions[0].prod[0], Reachable )
-
- for s in Nonterminals.keys():
- if not Reachable[s]:
- sys.stderr.write("yacc: Symbol '%s' is unreachable.\n" % s)
-
-def mark_reachable_from(s, Reachable):
- '''
- Mark all symbols that are reachable from symbol s.
- '''
- if Reachable[s]:
- # We've already reached symbol s.
- return
- Reachable[s] = 1
- for p in Prodnames.get(s,[]):
- for r in p.prod:
- mark_reachable_from(r, Reachable)
-
-# -----------------------------------------------------------------------------
-# compute_terminates()
-#
-# This function looks at the various parsing rules and tries to detect
-# infinite recursion cycles (grammar rules where there is no possible way
-# to derive a string of only terminals).
-# -----------------------------------------------------------------------------
-def compute_terminates():
- '''
- Raise an error for any symbols that don't terminate.
- '''
- Terminates = {}
-
- # Terminals:
- for t in Terminals.keys():
- Terminates[t] = 1
-
- Terminates['$end'] = 1
-
- # Nonterminals:
-
- # Initialize to false:
- for n in Nonterminals.keys():
- Terminates[n] = 0
-
- # Then propagate termination until no change:
- while 1:
- some_change = 0
- for (n,pl) in Prodnames.items():
- # Nonterminal n terminates iff any of its productions terminates.
- for p in pl:
- # Production p terminates iff all of its rhs symbols terminate.
- for s in p.prod:
- if not Terminates[s]:
- # The symbol s does not terminate,
- # so production p does not terminate.
- p_terminates = 0
- break
- else:
- # didn't break from the loop,
- # so every symbol s terminates
- # so production p terminates.
- p_terminates = 1
-
- if p_terminates:
- # symbol n terminates!
- if not Terminates[n]:
- Terminates[n] = 1
- some_change = 1
- # Don't need to consider any more productions for this n.
- break
-
- if not some_change:
- break
-
- some_error = 0
- for (s,terminates) in Terminates.items():
- if not terminates:
- if not Prodnames.has_key(s) and not Terminals.has_key(s) and s != 'error':
- # s is used-but-not-defined, and we've already warned of that,
- # so it would be overkill to say that it's also non-terminating.
- pass
- else:
- sys.stderr.write("yacc: Infinite recursion detected for symbol '%s'.\n" % s)
- some_error = 1
+ self.Follow = { } # A dictionary of precomputed FOLLOW(x) symbols
- return some_error
+ self.Precedence = { } # Precedence rules for each terminal. Contains tuples of the
+ # form ('right',level) or ('nonassoc', level) or ('left',level)
-# -----------------------------------------------------------------------------
-# verify_productions()
-#
-# This function examines all of the supplied rules to see if they seem valid.
-# -----------------------------------------------------------------------------
-def verify_productions(cycle_check=1):
- error = 0
- for p in Productions:
- if not p: continue
+ self.UsedPrecedence = { } # Precedence rules that were actually used by the grammer.
+ # This is only used to provide error checking and to generate
+ # a warning about unused precedence rules.
- for s in p.prod:
- if not Prodnames.has_key(s) and not Terminals.has_key(s) and s != 'error':
- sys.stderr.write("%s:%d: Symbol '%s' used, but not defined as a token or a rule.\n" % (p.file,p.line,s))
- error = 1
- continue
+ self.Start = None # Starting symbol for the grammar
- unused_tok = 0
- # Now verify all of the tokens
- if yaccdebug:
- _vf.write("Unused terminals:\n\n")
- for s,v in Terminals.items():
- if s != 'error' and not v:
- sys.stderr.write("yacc: Warning. Token '%s' defined, but not used.\n" % s)
- if yaccdebug: _vf.write(" %s\n"% s)
- unused_tok += 1
-
- # Print out all of the productions
- if yaccdebug:
- _vf.write("\nGrammar\n\n")
- for i in range(1,len(Productions)):
- _vf.write("Rule %-5d %s\n" % (i, Productions[i]))
-
- unused_prod = 0
- # Verify the use of all productions
- for s,v in Nonterminals.items():
- if not v:
- p = Prodnames[s][0]
- sys.stderr.write("%s:%d: Warning. Rule '%s' defined, but not used.\n" % (p.file,p.line, s))
- unused_prod += 1
-
-
- if unused_tok == 1:
- sys.stderr.write("yacc: Warning. There is 1 unused token.\n")
- if unused_tok > 1:
- sys.stderr.write("yacc: Warning. There are %d unused tokens.\n" % unused_tok)
-
- if unused_prod == 1:
- sys.stderr.write("yacc: Warning. There is 1 unused rule.\n")
- if unused_prod > 1:
- sys.stderr.write("yacc: Warning. There are %d unused rules.\n" % unused_prod)
-
- if yaccdebug:
- _vf.write("\nTerminals, with rules where they appear\n\n")
- ks = Terminals.keys()
- ks.sort()
- for k in ks:
- _vf.write("%-20s : %s\n" % (k, " ".join([str(s) for s in Terminals[k]])))
- _vf.write("\nNonterminals, with rules where they appear\n\n")
- ks = Nonterminals.keys()
- ks.sort()
- for k in ks:
- _vf.write("%-20s : %s\n" % (k, " ".join([str(s) for s in Nonterminals[k]])))
-
- if (cycle_check):
- compute_reachable()
- error += compute_terminates()
-# error += check_cycles()
- return error
-
-# -----------------------------------------------------------------------------
-# build_lritems()
-#
-# This function walks the list of productions and builds a complete set of the
-# LR items. The LR items are stored in two ways: First, they are uniquely
-# numbered and placed in the list _lritems. Second, a linked list of LR items
-# is built for each production. For example:
-#
-# E -> E PLUS E
-#
-# Creates the list
-#
-# [E -> . E PLUS E, E -> E . PLUS E, E -> E PLUS . E, E -> E PLUS E . ]
-# -----------------------------------------------------------------------------
-
-def build_lritems():
- for p in Productions:
- lastlri = p
- lri = p.lr_item(0)
- i = 0
- while 1:
- lri = p.lr_item(i)
- lastlri.lr_next = lri
- if not lri: break
- lri.lr_num = len(LRitems)
- LRitems.append(lri)
- lastlri = lri
- i += 1
- # In order for the rest of the parser generator to work, we need to
- # guarantee that no more lritems are generated. Therefore, we nuke
- # the p.lr_item method. (Only used in debugging)
- # Production.lr_item = None
+ def __len__(self):
+ return len(self.Productions)
-# -----------------------------------------------------------------------------
-# add_precedence()
-#
-# Given a list of precedence rules, add to the precedence table.
-# -----------------------------------------------------------------------------
+ def __getitem__(self,index):
+ return self.Productions[index]
-def add_precedence(plist):
- plevel = 0
- error = 0
- for p in plist:
- plevel += 1
- try:
- prec = p[0]
- terms = p[1:]
- if prec != 'left' and prec != 'right' and prec != 'nonassoc':
- sys.stderr.write("yacc: Invalid precedence '%s'\n" % prec)
- return -1
- for t in terms:
- if Precedence.has_key(t):
- sys.stderr.write("yacc: Precedence already specified for terminal '%s'\n" % t)
- error += 1
- continue
- Precedence[t] = (prec,plevel)
- except:
- sys.stderr.write("yacc: Invalid precedence table.\n")
- error += 1
+ # -----------------------------------------------------------------------------
+ # set_precedence()
+ #
+ # Sets the precedence for a given terminal. assoc is the associativity such as
+ # 'left','right', or 'nonassoc'. level is a numeric level.
+ #
+ # -----------------------------------------------------------------------------
- return error
+ def set_precedence(self,term,assoc,level):
+ assert self.Productions == [None],"Must call set_precedence() before add_production()"
+ if term in self.Precedence:
+ raise GrammarError("Precedence already specified for terminal '%s'" % term)
+ if assoc not in ['left','right','nonassoc']:
+ raise GrammarError("Associativity must be one of 'left','right', or 'nonassoc'")
+ self.Precedence[term] = (assoc,level)
+
+ # -----------------------------------------------------------------------------
+ # add_production()
+ #
+ # Given an action function, this function assembles a production rule and
+ # computes its precedence level.
+ #
+ # The production rule is supplied as a list of symbols. For example,
+ # a rule such as 'expr : expr PLUS term' has a production name of 'expr' and
+ # symbols ['expr','PLUS','term'].
+ #
+ # Precedence is determined by the precedence of the right-most non-terminal
+ # or the precedence of a terminal specified by %prec.
+ #
+ # A variety of error checks are performed to make sure production symbols
+ # are valid and that %prec is used correctly.
+ # -----------------------------------------------------------------------------
+
+ def add_production(self,prodname,syms,func=None,file='',line=0):
+
+ if prodname in self.Terminals:
+ raise GrammarError("%s:%d: Illegal rule name '%s'. Already defined as a token" % (file,line,prodname))
+ if prodname == 'error':
+ raise GrammarError("%s:%d: Illegal rule name '%s'. error is a reserved word" % (file,line,prodname))
+ if not _is_identifier.match(prodname):
+ raise GrammarError("%s:%d: Illegal rule name '%s'" % (file,line,prodname))
+
+ # Look for literal tokens
+ for n,s in enumerate(syms):
+ if s[0] in "'\"":
+ try:
+ c = eval(s)
+ if (len(c) > 1):
+ raise GrammarError("%s:%d: Literal token %s in rule '%s' may only be a single character" % (file,line,s, prodname))
+ if not c in self.Terminals:
+ self.Terminals[c] = []
+ syms[n] = c
+ continue
+ except SyntaxError:
+ pass
+ if not _is_identifier.match(s) and s != '%prec':
+ raise GrammarError("%s:%d: Illegal name '%s' in rule '%s'" % (file,line,s, prodname))
+
+ # Determine the precedence level
+ if '%prec' in syms:
+ if syms[-1] == '%prec':
+ raise GrammarError("%s:%d: Syntax error. Nothing follows %%prec" % (file,line))
+ if syms[-2] != '%prec':
+ raise GrammarError("%s:%d: Syntax error. %%prec can only appear at the end of a grammar rule" % (file,line))
+ precname = syms[-1]
+ prodprec = self.Precedence.get(precname,None)
+ if not prodprec:
+ raise GrammarError("%s:%d: Nothing known about the precedence of '%s'" % (file,line,precname))
+ else:
+ self.UsedPrecedence[precname] = 1
+ del syms[-2:] # Drop %prec from the rule
+ else:
+ # If no %prec, precedence is determined by the rightmost terminal symbol
+ precname = rightmost_terminal(syms,self.Terminals)
+ prodprec = self.Precedence.get(precname,('right',0))
+
+ # See if the rule is already in the rulemap
+ map = "%s -> %s" % (prodname,syms)
+ if map in self.Prodmap:
+ m = self.Prodmap[map]
+ raise GrammarError("%s:%d: Duplicate rule %s. " % (file,line, m) +
+ "Previous definition at %s:%d" % (m.file, m.line))
+
+ # From this point on, everything is valid. Create a new Production instance
+ pnumber = len(self.Productions)
+ if not prodname in self.Nonterminals:
+ self.Nonterminals[prodname] = [ ]
+
+ # Add the production number to Terminals and Nonterminals
+ for t in syms:
+ if t in self.Terminals:
+ self.Terminals[t].append(pnumber)
+ else:
+ if not t in self.Nonterminals:
+ self.Nonterminals[t] = [ ]
+ self.Nonterminals[t].append(pnumber)
+
+ # Create a production and add it to the list of productions
+ p = Production(pnumber,prodname,syms,prodprec,func,file,line)
+ self.Productions.append(p)
+ self.Prodmap[map] = p
-# -----------------------------------------------------------------------------
-# check_precedence()
-#
-# Checks the use of the Precedence tables. This makes sure all of the symbols
-# are terminals or were used with %prec
-# -----------------------------------------------------------------------------
+ # Add to the global productions list
+ try:
+ self.Prodnames[prodname].append(p)
+ except KeyError:
+ self.Prodnames[prodname] = [ p ]
+ return 0
-def check_precedence():
- error = 0
- for precname in Precedence.keys():
- if not (Terminals.has_key(precname) or UsedPrecedence.has_key(precname)):
- sys.stderr.write("yacc: Precedence rule '%s' defined for unknown symbol '%s'\n" % (Precedence[precname][0],precname))
- error += 1
- return error
+ # -----------------------------------------------------------------------------
+ # set_start()
+ #
+ # Sets the starting symbol and creates the augmented grammar. Production
+ # rule 0 is S' -> start where start is the start symbol.
+ # -----------------------------------------------------------------------------
+
+ def set_start(self,start=None):
+ if not start:
+ start = self.Productions[1].name
+ if start not in self.Nonterminals:
+ raise GrammarError("start symbol %s undefined" % start)
+ self.Productions[0] = Production(0,"S'",[start])
+ self.Nonterminals[start].append(0)
+ self.Start = start
-# -----------------------------------------------------------------------------
-# augment_grammar()
-#
-# Compute the augmented grammar. This is just a rule S' -> start where start
-# is the starting symbol.
-# -----------------------------------------------------------------------------
+ # -----------------------------------------------------------------------------
+ # find_unreachable()
+ #
+ # Find all of the nonterminal symbols that can't be reached from the starting
+ # symbol. Returns a list of nonterminals that can't be reached.
+ # -----------------------------------------------------------------------------
-def augment_grammar(start=None):
- if not start:
- start = Productions[1].name
- Productions[0] = Production(name="S'",prod=[start],number=0,len=1,prec=('right',0),func=None)
- Productions[0].usyms = [ start ]
- Nonterminals[start].append(0)
+ def find_unreachable(self):
+
+ # Mark all symbols that are reachable from a symbol s
+ def mark_reachable_from(s):
+ if reachable[s]:
+ # We've already reached symbol s.
+ return
+ reachable[s] = 1
+ for p in self.Prodnames.get(s,[]):
+ for r in p.prod:
+ mark_reachable_from(r)
+
+ reachable = { }
+ for s in list(self.Terminals) + list(self.Nonterminals):
+ reachable[s] = 0
+ mark_reachable_from( self.Productions[0].prod[0] )
-# -------------------------------------------------------------------------
-# first()
-#
-# Compute the value of FIRST1(beta) where beta is a tuple of symbols.
-#
-# During execution of compute_first1, the result may be incomplete.
-# Afterward (e.g., when called from compute_follow()), it will be complete.
-# -------------------------------------------------------------------------
-def first(beta):
+ return [s for s in list(self.Nonterminals)
+ if not reachable[s]]
+
+ # -----------------------------------------------------------------------------
+ # infinite_cycles()
+ #
+ # This function looks at the various parsing rules and tries to detect
+ # infinite recursion cycles (grammar rules where there is no possible way
+ # to derive a string of only terminals).
+ # -----------------------------------------------------------------------------
- # We are computing First(x1,x2,x3,...,xn)
- result = [ ]
- for x in beta:
- x_produces_empty = 0
+ def infinite_cycles(self):
+ terminates = {}
- # Add all the non-<empty> symbols of First[x] to the result.
- for f in First[x]:
- if f == '<empty>':
- x_produces_empty = 1
- else:
- if f not in result: result.append(f)
+ # Terminals:
+ for t in self.Terminals:
+ terminates[t] = 1
- if x_produces_empty:
- # We have to consider the next x in beta,
- # i.e. stay in the loop.
- pass
- else:
- # We don't have to consider any further symbols in beta.
- break
- else:
- # There was no 'break' from the loop,
- # so x_produces_empty was true for all x in beta,
- # so beta produces empty as well.
- result.append('<empty>')
+ terminates['$end'] = 1
- return result
+ # Nonterminals:
+ # Initialize to false:
+ for n in self.Nonterminals:
+ terminates[n] = 0
-# FOLLOW(x)
-# Given a non-terminal. This function computes the set of all symbols
-# that might follow it. Dragon book, p. 189.
-
-def compute_follow(start=None):
- # Add '$end' to the follow list of the start symbol
- for k in Nonterminals.keys():
- Follow[k] = [ ]
-
- if not start:
- start = Productions[1].name
-
- Follow[start] = [ '$end' ]
-
- while 1:
- didadd = 0
- for p in Productions[1:]:
- # Here is the production set
- for i in range(len(p.prod)):
- B = p.prod[i]
- if Nonterminals.has_key(B):
- # Okay. We got a non-terminal in a production
- fst = first(p.prod[i+1:])
- hasempty = 0
- for f in fst:
- if f != '<empty>' and f not in Follow[B]:
- Follow[B].append(f)
- didadd = 1
- if f == '<empty>':
- hasempty = 1
- if hasempty or i == (len(p.prod)-1):
- # Add elements of follow(a) to follow(b)
- for f in Follow[p.name]:
- if f not in Follow[B]:
- Follow[B].append(f)
- didadd = 1
- if not didadd: break
-
- if 0 and yaccdebug:
- _vf.write('\nFollow:\n')
- for k in Nonterminals.keys():
- _vf.write("%-20s : %s\n" % (k, " ".join([str(s) for s in Follow[k]])))
-
-# -------------------------------------------------------------------------
-# compute_first1()
-#
-# Compute the value of FIRST1(X) for all symbols
-# -------------------------------------------------------------------------
-def compute_first1():
-
- # Terminals:
- for t in Terminals.keys():
- First[t] = [t]
-
- First['$end'] = ['$end']
- First['#'] = ['#'] # what's this for?
-
- # Nonterminals:
-
- # Initialize to the empty set:
- for n in Nonterminals.keys():
- First[n] = []
-
- # Then propagate symbols until no change:
- while 1:
- some_change = 0
- for n in Nonterminals.keys():
- for p in Prodnames[n]:
- for f in first(p.prod):
- if f not in First[n]:
- First[n].append( f )
- some_change = 1
- if not some_change:
- break
-
- if 0 and yaccdebug:
- _vf.write('\nFirst:\n')
- for k in Nonterminals.keys():
- _vf.write("%-20s : %s\n" %
- (k, " ".join([str(s) for s in First[k]])))
-
-# -----------------------------------------------------------------------------
-# === SLR Generation ===
-#
-# The following functions are used to construct SLR (Simple LR) parsing tables
-# as described on p.221-229 of the dragon book.
-# -----------------------------------------------------------------------------
-
-# Global variables for the LR parsing engine
-def lr_init_vars():
- global _lr_action, _lr_goto, _lr_method
- global _lr_goto_cache, _lr0_cidhash
-
- _lr_action = { } # Action table
- _lr_goto = { } # Goto table
- _lr_method = "Unknown" # LR method used
- _lr_goto_cache = { }
- _lr0_cidhash = { }
-
-
-# Compute the LR(0) closure operation on I, where I is a set of LR(0) items.
-# prodlist is a list of productions.
-
-_add_count = 0 # Counter used to detect cycles
-
-def lr0_closure(I):
- global _add_count
-
- _add_count += 1
- prodlist = Productions
-
- # Add everything in I to J
- J = I[:]
- didadd = 1
- while didadd:
- didadd = 0
- for j in J:
- for x in j.lrafter:
- if x.lr0_added == _add_count: continue
- # Add B --> .G to J
- J.append(x.lr_next)
- x.lr0_added = _add_count
- didadd = 1
-
- return J
-
-# Compute the LR(0) goto function goto(I,X) where I is a set
-# of LR(0) items and X is a grammar symbol. This function is written
-# in a way that guarantees uniqueness of the generated goto sets
-# (i.e. the same goto set will never be returned as two different Python
-# objects). With uniqueness, we can later do fast set comparisons using
-# id(obj) instead of element-wise comparison.
-
-def lr0_goto(I,x):
- # First we look for a previously cached entry
- g = _lr_goto_cache.get((id(I),x),None)
- if g: return g
-
- # Now we generate the goto set in a way that guarantees uniqueness
- # of the result
-
- s = _lr_goto_cache.get(x,None)
- if not s:
- s = { }
- _lr_goto_cache[x] = s
-
- gs = [ ]
- for p in I:
- n = p.lr_next
- if n and n.lrbefore == x:
- s1 = s.get(id(n),None)
- if not s1:
- s1 = { }
- s[id(n)] = s1
- gs.append(n)
- s = s1
- g = s.get('$end',None)
- if not g:
- if gs:
- g = lr0_closure(gs)
- s['$end'] = g
- else:
- s['$end'] = gs
- _lr_goto_cache[(id(I),x)] = g
- return g
-
-_lr0_cidhash = { }
+ # Then propagate termination until no change:
+ while 1:
+ some_change = 0
+ for (n,pl) in self.Prodnames.items():
+ # Nonterminal n terminates iff any of its productions terminates.
+ for p in pl:
+ # Production p terminates iff all of its rhs symbols terminate.
+ for s in p.prod:
+ if not terminates[s]:
+ # The symbol s does not terminate,
+ # so production p does not terminate.
+ p_terminates = 0
+ break
+ else:
+ # didn't break from the loop,
+ # so every symbol s terminates
+ # so production p terminates.
+ p_terminates = 1
+
+ if p_terminates:
+ # symbol n terminates!
+ if not terminates[n]:
+ terminates[n] = 1
+ some_change = 1
+ # Don't need to consider any more productions for this n.
+ break
-# Compute the LR(0) sets of item function
-def lr0_items():
+ if not some_change:
+ break
- C = [ lr0_closure([Productions[0].lr_next]) ]
- i = 0
- for I in C:
- _lr0_cidhash[id(I)] = i
- i += 1
+ infinite = []
+ for (s,term) in terminates.items():
+ if not term:
+ if not s in self.Prodnames and not s in self.Terminals and s != 'error':
+ # s is used-but-not-defined, and we've already warned of that,
+ # so it would be overkill to say that it's also non-terminating.
+ pass
+ else:
+ infinite.append(s)
- # Loop over the items in C and each grammar symbols
- i = 0
- while i < len(C):
- I = C[i]
- i += 1
+ return infinite
- # Collect all of the symbols that could possibly be in the goto(I,X) sets
- asyms = { }
- for ii in I:
- for s in ii.usyms:
- asyms[s] = None
- for x in asyms.keys():
- g = lr0_goto(I,x)
- if not g: continue
- if _lr0_cidhash.has_key(id(g)): continue
- _lr0_cidhash[id(g)] = len(C)
- C.append(g)
+ # -----------------------------------------------------------------------------
+ # undefined_symbols()
+ #
+ # Find all symbols that were used the grammar, but not defined as tokens or
+ # grammar rules. Returns a list of tuples (sym, prod) where sym in the symbol
+ # and prod is the production where the symbol was used.
+ # -----------------------------------------------------------------------------
+ def undefined_symbols(self):
+ result = []
+ for p in self.Productions:
+ if not p: continue
- return C
+ for s in p.prod:
+ if not s in self.Prodnames and not s in self.Terminals and s != 'error':
+ result.append((s,p))
+ return result
-# -----------------------------------------------------------------------------
-# ==== LALR(1) Parsing ====
-#
-# LALR(1) parsing is almost exactly the same as SLR except that instead of
-# relying upon Follow() sets when performing reductions, a more selective
-# lookahead set that incorporates the state of the LR(0) machine is utilized.
-# Thus, we mainly just have to focus on calculating the lookahead sets.
-#
-# The method used here is due to DeRemer and Pennelo (1982).
-#
-# DeRemer, F. L., and T. J. Pennelo: "Efficient Computation of LALR(1)
-# Lookahead Sets", ACM Transactions on Programming Languages and Systems,
-# Vol. 4, No. 4, Oct. 1982, pp. 615-649
-#
-# Further details can also be found in:
-#
-# J. Tremblay and P. Sorenson, "The Theory and Practice of Compiler Writing",
-# McGraw-Hill Book Company, (1985).
-#
-# Note: This implementation is a complete replacement of the LALR(1)
-# implementation in PLY-1.x releases. That version was based on
-# a less efficient algorithm and it had bugs in its implementation.
-# -----------------------------------------------------------------------------
+ # -----------------------------------------------------------------------------
+ # unused_terminals()
+ #
+ # Find all terminals that were defined, but not used by the grammar. Returns
+ # a list of all symbols.
+ # -----------------------------------------------------------------------------
+ def unused_terminals(self):
+ unused_tok = []
+ for s,v in self.Terminals.items():
+ if s != 'error' and not v:
+ unused_tok.append(s)
-# -----------------------------------------------------------------------------
-# compute_nullable_nonterminals()
-#
-# Creates a dictionary containing all of the non-terminals that might produce
-# an empty production.
-# -----------------------------------------------------------------------------
+ return unused_tok
-def compute_nullable_nonterminals():
- nullable = {}
- num_nullable = 0
- while 1:
- for p in Productions[1:]:
- if p.len == 0:
- nullable[p.name] = 1
- continue
- for t in p.prod:
- if not nullable.has_key(t): break
- else:
- nullable[p.name] = 1
- if len(nullable) == num_nullable: break
- num_nullable = len(nullable)
- return nullable
+ # ------------------------------------------------------------------------------
+ # unused_rules()
+ #
+ # Find all grammar rules that were defined, but not used (maybe not reachable)
+ # Returns a list of productions.
+ # ------------------------------------------------------------------------------
+
+ def unused_rules(self):
+ unused_prod = []
+ for s,v in self.Nonterminals.items():
+ if not v:
+ p = self.Prodnames[s][0]
+ unused_prod.append(p)
+ return unused_prod
-# -----------------------------------------------------------------------------
-# find_nonterminal_trans(C)
-#
-# Given a set of LR(0) items, this functions finds all of the non-terminal
-# transitions. These are transitions in which a dot appears immediately before
-# a non-terminal. Returns a list of tuples of the form (state,N) where state
-# is the state number and N is the nonterminal symbol.
-#
-# The input C is the set of LR(0) items.
-# -----------------------------------------------------------------------------
+ # -----------------------------------------------------------------------------
+ # unused_precedence()
+ #
+ # Returns a list of tuples (term,precedence) corresponding to precedence
+ # rules that were never used by the grammar. term is the name of the terminal
+ # on which precedence was applied and precedence is a string such as 'left' or
+ # 'right' corresponding to the type of precedence.
+ # -----------------------------------------------------------------------------
+
+ def unused_precedence(self):
+ unused = []
+ for termname in self.Precedence:
+ if not (termname in self.Terminals or termname in self.UsedPrecedence):
+ unused.append((termname,self.Precedence[termname][0]))
+
+ return unused
-def find_nonterminal_transitions(C):
- trans = []
- for state in range(len(C)):
- for p in C[state]:
- if p.lr_index < p.len - 1:
- t = (state,p.prod[p.lr_index+1])
- if Nonterminals.has_key(t[1]):
- if t not in trans: trans.append(t)
- state = state + 1
- return trans
+ # -------------------------------------------------------------------------
+ # _first()
+ #
+ # Compute the value of FIRST1(beta) where beta is a tuple of symbols.
+ #
+ # During execution of compute_first1, the result may be incomplete.
+ # Afterward (e.g., when called from compute_follow()), it will be complete.
+ # -------------------------------------------------------------------------
+ def _first(self,beta):
+
+ # We are computing First(x1,x2,x3,...,xn)
+ result = [ ]
+ for x in beta:
+ x_produces_empty = 0
+
+ # Add all the non-<empty> symbols of First[x] to the result.
+ for f in self.First[x]:
+ if f == '<empty>':
+ x_produces_empty = 1
+ else:
+ if f not in result: result.append(f)
-# -----------------------------------------------------------------------------
-# dr_relation()
-#
-# Computes the DR(p,A) relationships for non-terminal transitions. The input
-# is a tuple (state,N) where state is a number and N is a nonterminal symbol.
-#
-# Returns a list of terminals.
-# -----------------------------------------------------------------------------
+ if x_produces_empty:
+ # We have to consider the next x in beta,
+ # i.e. stay in the loop.
+ pass
+ else:
+ # We don't have to consider any further symbols in beta.
+ break
+ else:
+ # There was no 'break' from the loop,
+ # so x_produces_empty was true for all x in beta,
+ # so beta produces empty as well.
+ result.append('<empty>')
-def dr_relation(C,trans,nullable):
- dr_set = { }
- state,N = trans
- terms = []
+ return result
- g = lr0_goto(C[state],N)
- for p in g:
- if p.lr_index < p.len - 1:
- a = p.prod[p.lr_index+1]
- if Terminals.has_key(a):
- if a not in terms: terms.append(a)
+ # -------------------------------------------------------------------------
+ # compute_first()
+ #
+ # Compute the value of FIRST1(X) for all symbols
+ # -------------------------------------------------------------------------
+ def compute_first(self):
+ if self.First:
+ return self.First
- # This extra bit is to handle the start state
- if state == 0 and N == Productions[0].prod[0]:
- terms.append('$end')
+ # Terminals:
+ for t in self.Terminals:
+ self.First[t] = [t]
- return terms
+ self.First['$end'] = ['$end']
-# -----------------------------------------------------------------------------
-# reads_relation()
-#
-# Computes the READS() relation (p,A) READS (t,C).
-# -----------------------------------------------------------------------------
+ # Nonterminals:
-def reads_relation(C, trans, empty):
- # Look for empty transitions
- rel = []
- state, N = trans
+ # Initialize to the empty set:
+ for n in self.Nonterminals:
+ self.First[n] = []
- g = lr0_goto(C[state],N)
- j = _lr0_cidhash.get(id(g),-1)
- for p in g:
- if p.lr_index < p.len - 1:
- a = p.prod[p.lr_index + 1]
- if empty.has_key(a):
- rel.append((j,a))
+ # Then propagate symbols until no change:
+ while 1:
+ some_change = 0
+ for n in self.Nonterminals:
+ for p in self.Prodnames[n]:
+ for f in self._first(p.prod):
+ if f not in self.First[n]:
+ self.First[n].append( f )
+ some_change = 1
+ if not some_change:
+ break
+
+ return self.First
- return rel
+ # ---------------------------------------------------------------------
+ # compute_follow()
+ #
+ # Computes all of the follow sets for every non-terminal symbol. The
+ # follow set is the set of all symbols that might follow a given
+ # non-terminal. See the Dragon book, 2nd Ed. p. 189.
+ # ---------------------------------------------------------------------
+ def compute_follow(self,start=None):
+ # If already computed, return the result
+ if self.Follow:
+ return self.Follow
+
+ # If first sets not computed yet, do that first.
+ if not self.First:
+ self.compute_first()
+
+ # Add '$end' to the follow list of the start symbol
+ for k in self.Nonterminals:
+ self.Follow[k] = [ ]
-# -----------------------------------------------------------------------------
-# compute_lookback_includes()
-#
-# Determines the lookback and includes relations
-#
-# LOOKBACK:
-#
-# This relation is determined by running the LR(0) state machine forward.
-# For example, starting with a production "N : . A B C", we run it forward
-# to obtain "N : A B C ." We then build a relationship between this final
-# state and the starting state. These relationships are stored in a dictionary
-# lookdict.
-#
-# INCLUDES:
-#
-# Computes the INCLUDE() relation (p,A) INCLUDES (p',B).
-#
-# This relation is used to determine non-terminal transitions that occur
-# inside of other non-terminal transition states. (p,A) INCLUDES (p', B)
-# if the following holds:
-#
-# B -> LAT, where T -> epsilon and p' -L-> p
-#
-# L is essentially a prefix (which may be empty), T is a suffix that must be
-# able to derive an empty string. State p' must lead to state p with the string L.
-#
-# -----------------------------------------------------------------------------
+ if not start:
+ start = self.Productions[1].name
-def compute_lookback_includes(C,trans,nullable):
+ self.Follow[start] = [ '$end' ]
- lookdict = {} # Dictionary of lookback relations
- includedict = {} # Dictionary of include relations
+ while 1:
+ didadd = 0
+ for p in self.Productions[1:]:
+ # Here is the production set
+ for i in range(len(p.prod)):
+ B = p.prod[i]
+ if B in self.Nonterminals:
+ # Okay. We got a non-terminal in a production
+ fst = self._first(p.prod[i+1:])
+ hasempty = 0
+ for f in fst:
+ if f != '<empty>' and f not in self.Follow[B]:
+ self.Follow[B].append(f)
+ didadd = 1
+ if f == '<empty>':
+ hasempty = 1
+ if hasempty or i == (len(p.prod)-1):
+ # Add elements of follow(a) to follow(b)
+ for f in self.Follow[p.name]:
+ if f not in self.Follow[B]:
+ self.Follow[B].append(f)
+ didadd = 1
+ if not didadd: break
+ return self.Follow
- # Make a dictionary of non-terminal transitions
- dtrans = {}
- for t in trans:
- dtrans[t] = 1
- # Loop over all transitions and compute lookbacks and includes
- for state,N in trans:
- lookb = []
- includes = []
- for p in C[state]:
- if p.name != N: continue
+ # -----------------------------------------------------------------------------
+ # build_lritems()
+ #
+ # This function walks the list of productions and builds a complete set of the
+ # LR items. The LR items are stored in two ways: First, they are uniquely
+ # numbered and placed in the list _lritems. Second, a linked list of LR items
+ # is built for each production. For example:
+ #
+ # E -> E PLUS E
+ #
+ # Creates the list
+ #
+ # [E -> . E PLUS E, E -> E . PLUS E, E -> E PLUS . E, E -> E PLUS E . ]
+ # -----------------------------------------------------------------------------
- # Okay, we have a name match. We now follow the production all the way
- # through the state machine until we get the . on the right hand side
+ def build_lritems(self):
+ for p in self.Productions:
+ lastlri = p
+ i = 0
+ lr_items = []
+ while 1:
+ if i > len(p):
+ lri = None
+ else:
+ lri = LRItem(p,i)
+ # Precompute the list of productions immediately following
+ try:
+ lri.lr_after = self.Prodnames[lri.prod[i+1]]
+ except (IndexError,KeyError):
+ lri.lr_after = []
+ try:
+ lri.lr_before = lri.prod[i-1]
+ except IndexError:
+ lri.lr_before = None
+
+ lastlri.lr_next = lri
+ if not lri: break
+ lr_items.append(lri)
+ lastlri = lri
+ i += 1
+ p.lr_items = lr_items
+
+# -----------------------------------------------------------------------------
+# == Class LRTable ==
+#
+# This basic class represents a basic table of LR parsing information.
+# Methods for generating the tables are not defined here. They are defined
+# in the derived class LRGeneratedTable.
+# -----------------------------------------------------------------------------
+
+class VersionError(YaccError): pass
+
+class LRTable(object):
+ def __init__(self):
+ self.lr_action = None
+ self.lr_goto = None
+ self.lr_productions = None
+ self.lr_method = None
- lr_index = p.lr_index
- j = state
- while lr_index < p.len - 1:
- lr_index = lr_index + 1
- t = p.prod[lr_index]
+ def read_table(self,module):
+ if isinstance(module,types.ModuleType):
+ parsetab = module
+ else:
+ if sys.version_info[0] < 3:
+ exec("import %s as parsetab" % module)
+ else:
+ env = { }
+ exec("import %s as parsetab" % module, env, env)
+ parsetab = env['parsetab']
- # Check to see if this symbol and state are a non-terminal transition
- if dtrans.has_key((j,t)):
- # Yes. Okay, there is some chance that this is an includes relation
- # the only way to know for certain is whether the rest of the
- # production derives empty
+ if parsetab._tabversion != __tabversion__:
+ raise VersionError("yacc table file version is out of date")
- li = lr_index + 1
- while li < p.len:
- if Terminals.has_key(p.prod[li]): break # No forget it
- if not nullable.has_key(p.prod[li]): break
- li = li + 1
- else:
- # Appears to be a relation between (j,t) and (state,N)
- includes.append((j,t))
+ self.lr_action = parsetab._lr_action
+ self.lr_goto = parsetab._lr_goto
- g = lr0_goto(C[j],t) # Go to next set
- j = _lr0_cidhash.get(id(g),-1) # Go to next state
+ self.lr_productions = []
+ for p in parsetab._lr_productions:
+ self.lr_productions.append(MiniProduction(*p))
- # When we get here, j is the final state, now we have to locate the production
- for r in C[j]:
- if r.name != p.name: continue
- if r.len != p.len: continue
- i = 0
- # This look is comparing a production ". A B C" with "A B C ."
- while i < r.lr_index:
- if r.prod[i] != p.prod[i+1]: break
- i = i + 1
- else:
- lookb.append((j,r))
- for i in includes:
- if not includedict.has_key(i): includedict[i] = []
- includedict[i].append((state,N))
- lookdict[(state,N)] = lookb
+ self.lr_method = parsetab._lr_method
+ return parsetab._lr_signature
- return lookdict,includedict
+ def read_pickle(self,filename):
+ try:
+ import cPickle as pickle
+ except ImportError:
+ import pickle
+
+ in_f = open(filename,"rb")
+
+ tabversion = pickle.load(in_f)
+ if tabversion != __tabversion__:
+ raise VersionError("yacc table file version is out of date")
+ self.lr_method = pickle.load(in_f)
+ signature = pickle.load(in_f)
+ self.lr_action = pickle.load(in_f)
+ self.lr_goto = pickle.load(in_f)
+ productions = pickle.load(in_f)
+
+ self.lr_productions = []
+ for p in productions:
+ self.lr_productions.append(MiniProduction(*p))
+
+ in_f.close()
+ return signature
+
+ # Bind all production function names to callable objects in pdict
+ def bind_callables(self,pdict):
+ for p in self.lr_productions:
+ p.bind(pdict)
+
+# -----------------------------------------------------------------------------
+# === LR Generator ===
+#
+# The following classes and functions are used to generate LR parsing tables on
+# a grammar.
+# -----------------------------------------------------------------------------
# -----------------------------------------------------------------------------
# digraph()
@@ -2181,715 +1919,1358 @@
for a in F.get(y,[]):
if a not in F[x]: F[x].append(a)
if N[x] == d:
- N[stack[-1]] = sys.maxint
+ N[stack[-1]] = MAXINT
F[stack[-1]] = F[x]
element = stack.pop()
while element != x:
- N[stack[-1]] = sys.maxint
+ N[stack[-1]] = MAXINT
F[stack[-1]] = F[x]
element = stack.pop()
+class LALRError(YaccError): pass
+
# -----------------------------------------------------------------------------
-# compute_read_sets()
+# == LRGeneratedTable ==
#
-# Given a set of LR(0) items, this function computes the read sets.
-#
-# Inputs: C = Set of LR(0) items
-# ntrans = Set of nonterminal transitions
-# nullable = Set of empty transitions
-#
-# Returns a set containing the read sets
+# This class implements the LR table generation algorithm. There are no
+# public methods except for write()
# -----------------------------------------------------------------------------
-def compute_read_sets(C, ntrans, nullable):
- FP = lambda x: dr_relation(C,x,nullable)
- R = lambda x: reads_relation(C,x,nullable)
- F = digraph(ntrans,R,FP)
- return F
+class LRGeneratedTable(LRTable):
+ def __init__(self,grammar,method='LALR',log=None):
+ if method not in ['SLR','LALR']:
+ raise LALRError("Unsupported method %s" % method)
+
+ self.grammar = grammar
+ self.lr_method = method
+
+ # Set up the logger
+ if not log:
+ log = NullLogger()
+ self.log = log
+
+ # Internal attributes
+ self.lr_action = {} # Action table
+ self.lr_goto = {} # Goto table
+ self.lr_productions = grammar.Productions # Copy of grammar Production array
+ self.lr_goto_cache = {} # Cache of computed gotos
+ self.lr0_cidhash = {} # Cache of closures
+
+ self._add_count = 0 # Internal counter used to detect cycles
+
+ # Diagonistic information filled in by the table generator
+ self.sr_conflict = 0
+ self.rr_conflict = 0
+ self.conflicts = [] # List of conflicts
+
+ self.sr_conflicts = []
+ self.rr_conflicts = []
+
+ # Build the tables
+ self.grammar.build_lritems()
+ self.grammar.compute_first()
+ self.grammar.compute_follow()
+ self.lr_parse_table()
+
+ # Compute the LR(0) closure operation on I, where I is a set of LR(0) items.
+
+ def lr0_closure(self,I):
+ self._add_count += 1
+
+ # Add everything in I to J
+ J = I[:]
+ didadd = 1
+ while didadd:
+ didadd = 0
+ for j in J:
+ for x in j.lr_after:
+ if getattr(x,"lr0_added",0) == self._add_count: continue
+ # Add B --> .G to J
+ J.append(x.lr_next)
+ x.lr0_added = self._add_count
+ didadd = 1
+
+ return J
+
+ # Compute the LR(0) goto function goto(I,X) where I is a set
+ # of LR(0) items and X is a grammar symbol. This function is written
+ # in a way that guarantees uniqueness of the generated goto sets
+ # (i.e. the same goto set will never be returned as two different Python
+ # objects). With uniqueness, we can later do fast set comparisons using
+ # id(obj) instead of element-wise comparison.
+
+ def lr0_goto(self,I,x):
+ # First we look for a previously cached entry
+ g = self.lr_goto_cache.get((id(I),x),None)
+ if g: return g
+
+ # Now we generate the goto set in a way that guarantees uniqueness
+ # of the result
+
+ s = self.lr_goto_cache.get(x,None)
+ if not s:
+ s = { }
+ self.lr_goto_cache[x] = s
-# -----------------------------------------------------------------------------
-# compute_follow_sets()
-#
-# Given a set of LR(0) items, a set of non-terminal transitions, a readset,
-# and an include set, this function computes the follow sets
-#
-# Follow(p,A) = Read(p,A) U U {Follow(p',B) | (p,A) INCLUDES (p',B)}
-#
-# Inputs:
-# ntrans = Set of nonterminal transitions
-# readsets = Readset (previously computed)
-# inclsets = Include sets (previously computed)
-#
-# Returns a set containing the follow sets
-# -----------------------------------------------------------------------------
+ gs = [ ]
+ for p in I:
+ n = p.lr_next
+ if n and n.lr_before == x:
+ s1 = s.get(id(n),None)
+ if not s1:
+ s1 = { }
+ s[id(n)] = s1
+ gs.append(n)
+ s = s1
+ g = s.get('$end',None)
+ if not g:
+ if gs:
+ g = self.lr0_closure(gs)
+ s['$end'] = g
+ else:
+ s['$end'] = gs
+ self.lr_goto_cache[(id(I),x)] = g
+ return g
-def compute_follow_sets(ntrans,readsets,inclsets):
- FP = lambda x: readsets[x]
- R = lambda x: inclsets.get(x,[])
- F = digraph(ntrans,R,FP)
- return F
+ # Compute the LR(0) sets of item function
+ def lr0_items(self):
-# -----------------------------------------------------------------------------
-# add_lookaheads()
-#
-# Attaches the lookahead symbols to grammar rules.
-#
-# Inputs: lookbacks - Set of lookback relations
-# followset - Computed follow set
-#
-# This function directly attaches the lookaheads to productions contained
-# in the lookbacks set
-# -----------------------------------------------------------------------------
+ C = [ self.lr0_closure([self.grammar.Productions[0].lr_next]) ]
+ i = 0
+ for I in C:
+ self.lr0_cidhash[id(I)] = i
+ i += 1
+
+ # Loop over the items in C and each grammar symbols
+ i = 0
+ while i < len(C):
+ I = C[i]
+ i += 1
-def add_lookaheads(lookbacks,followset):
- for trans,lb in lookbacks.items():
- # Loop over productions in lookback
- for state,p in lb:
- if not p.lookaheads.has_key(state):
- p.lookaheads[state] = []
- f = followset.get(trans,[])
- for a in f:
- if a not in p.lookaheads[state]: p.lookaheads[state].append(a)
+ # Collect all of the symbols that could possibly be in the goto(I,X) sets
+ asyms = { }
+ for ii in I:
+ for s in ii.usyms:
+ asyms[s] = None
+
+ for x in asyms:
+ g = self.lr0_goto(I,x)
+ if not g: continue
+ if id(g) in self.lr0_cidhash: continue
+ self.lr0_cidhash[id(g)] = len(C)
+ C.append(g)
-# -----------------------------------------------------------------------------
-# add_lalr_lookaheads()
-#
-# This function does all of the work of adding lookahead information for use
-# with LALR parsing
-# -----------------------------------------------------------------------------
+ return C
+
+ # -----------------------------------------------------------------------------
+ # ==== LALR(1) Parsing ====
+ #
+ # LALR(1) parsing is almost exactly the same as SLR except that instead of
+ # relying upon Follow() sets when performing reductions, a more selective
+ # lookahead set that incorporates the state of the LR(0) machine is utilized.
+ # Thus, we mainly just have to focus on calculating the lookahead sets.
+ #
+ # The method used here is due to DeRemer and Pennelo (1982).
+ #
+ # DeRemer, F. L., and T. J. Pennelo: "Efficient Computation of LALR(1)
+ # Lookahead Sets", ACM Transactions on Programming Languages and Systems,
+ # Vol. 4, No. 4, Oct. 1982, pp. 615-649
+ #
+ # Further details can also be found in:
+ #
+ # J. Tremblay and P. Sorenson, "The Theory and Practice of Compiler Writing",
+ # McGraw-Hill Book Company, (1985).
+ #
+ # -----------------------------------------------------------------------------
+
+ # -----------------------------------------------------------------------------
+ # compute_nullable_nonterminals()
+ #
+ # Creates a dictionary containing all of the non-terminals that might produce
+ # an empty production.
+ # -----------------------------------------------------------------------------
+
+ def compute_nullable_nonterminals(self):
+ nullable = {}
+ num_nullable = 0
+ while 1:
+ for p in self.grammar.Productions[1:]:
+ if p.len == 0:
+ nullable[p.name] = 1
+ continue
+ for t in p.prod:
+ if not t in nullable: break
+ else:
+ nullable[p.name] = 1
+ if len(nullable) == num_nullable: break
+ num_nullable = len(nullable)
+ return nullable
-def add_lalr_lookaheads(C):
- # Determine all of the nullable nonterminals
- nullable = compute_nullable_nonterminals()
+ # -----------------------------------------------------------------------------
+ # find_nonterminal_trans(C)
+ #
+ # Given a set of LR(0) items, this functions finds all of the non-terminal
+ # transitions. These are transitions in which a dot appears immediately before
+ # a non-terminal. Returns a list of tuples of the form (state,N) where state
+ # is the state number and N is the nonterminal symbol.
+ #
+ # The input C is the set of LR(0) items.
+ # -----------------------------------------------------------------------------
- # Find all non-terminal transitions
- trans = find_nonterminal_transitions(C)
+ def find_nonterminal_transitions(self,C):
+ trans = []
+ for state in range(len(C)):
+ for p in C[state]:
+ if p.lr_index < p.len - 1:
+ t = (state,p.prod[p.lr_index+1])
+ if t[1] in self.grammar.Nonterminals:
+ if t not in trans: trans.append(t)
+ state = state + 1
+ return trans
- # Compute read sets
- readsets = compute_read_sets(C,trans,nullable)
+ # -----------------------------------------------------------------------------
+ # dr_relation()
+ #
+ # Computes the DR(p,A) relationships for non-terminal transitions. The input
+ # is a tuple (state,N) where state is a number and N is a nonterminal symbol.
+ #
+ # Returns a list of terminals.
+ # -----------------------------------------------------------------------------
- # Compute lookback/includes relations
- lookd, included = compute_lookback_includes(C,trans,nullable)
+ def dr_relation(self,C,trans,nullable):
+ dr_set = { }
+ state,N = trans
+ terms = []
+
+ g = self.lr0_goto(C[state],N)
+ for p in g:
+ if p.lr_index < p.len - 1:
+ a = p.prod[p.lr_index+1]
+ if a in self.grammar.Terminals:
+ if a not in terms: terms.append(a)
+
+ # This extra bit is to handle the start state
+ if state == 0 and N == self.grammar.Productions[0].prod[0]:
+ terms.append('$end')
- # Compute LALR FOLLOW sets
- followsets = compute_follow_sets(trans,readsets,included)
+ return terms
- # Add all of the lookaheads
- add_lookaheads(lookd,followsets)
+ # -----------------------------------------------------------------------------
+ # reads_relation()
+ #
+ # Computes the READS() relation (p,A) READS (t,C).
+ # -----------------------------------------------------------------------------
-# -----------------------------------------------------------------------------
-# lr_parse_table()
-#
-# This function constructs the parse tables for SLR or LALR
-# -----------------------------------------------------------------------------
-def lr_parse_table(method):
- global _lr_method
- goto = _lr_goto # Goto array
- action = _lr_action # Action array
- actionp = { } # Action production array (temporary)
+ def reads_relation(self,C, trans, empty):
+ # Look for empty transitions
+ rel = []
+ state, N = trans
+
+ g = self.lr0_goto(C[state],N)
+ j = self.lr0_cidhash.get(id(g),-1)
+ for p in g:
+ if p.lr_index < p.len - 1:
+ a = p.prod[p.lr_index + 1]
+ if a in empty:
+ rel.append((j,a))
- _lr_method = method
+ return rel
- n_srconflict = 0
- n_rrconflict = 0
+ # -----------------------------------------------------------------------------
+ # compute_lookback_includes()
+ #
+ # Determines the lookback and includes relations
+ #
+ # LOOKBACK:
+ #
+ # This relation is determined by running the LR(0) state machine forward.
+ # For example, starting with a production "N : . A B C", we run it forward
+ # to obtain "N : A B C ." We then build a relationship between this final
+ # state and the starting state. These relationships are stored in a dictionary
+ # lookdict.
+ #
+ # INCLUDES:
+ #
+ # Computes the INCLUDE() relation (p,A) INCLUDES (p',B).
+ #
+ # This relation is used to determine non-terminal transitions that occur
+ # inside of other non-terminal transition states. (p,A) INCLUDES (p', B)
+ # if the following holds:
+ #
+ # B -> LAT, where T -> epsilon and p' -L-> p
+ #
+ # L is essentially a prefix (which may be empty), T is a suffix that must be
+ # able to derive an empty string. State p' must lead to state p with the string L.
+ #
+ # -----------------------------------------------------------------------------
- if yaccdebug:
- sys.stderr.write("yacc: Generating %s parsing table...\n" % method)
- _vf.write("\n\nParsing method: %s\n\n" % method)
+ def compute_lookback_includes(self,C,trans,nullable):
- # Step 1: Construct C = { I0, I1, ... IN}, collection of LR(0) items
- # This determines the number of states
+ lookdict = {} # Dictionary of lookback relations
+ includedict = {} # Dictionary of include relations
- C = lr0_items()
+ # Make a dictionary of non-terminal transitions
+ dtrans = {}
+ for t in trans:
+ dtrans[t] = 1
+
+ # Loop over all transitions and compute lookbacks and includes
+ for state,N in trans:
+ lookb = []
+ includes = []
+ for p in C[state]:
+ if p.name != N: continue
+
+ # Okay, we have a name match. We now follow the production all the way
+ # through the state machine until we get the . on the right hand side
+
+ lr_index = p.lr_index
+ j = state
+ while lr_index < p.len - 1:
+ lr_index = lr_index + 1
+ t = p.prod[lr_index]
+
+ # Check to see if this symbol and state are a non-terminal transition
+ if (j,t) in dtrans:
+ # Yes. Okay, there is some chance that this is an includes relation
+ # the only way to know for certain is whether the rest of the
+ # production derives empty
+
+ li = lr_index + 1
+ while li < p.len:
+ if p.prod[li] in self.grammar.Terminals: break # No forget it
+ if not p.prod[li] in nullable: break
+ li = li + 1
+ else:
+ # Appears to be a relation between (j,t) and (state,N)
+ includes.append((j,t))
+
+ g = self.lr0_goto(C[j],t) # Go to next set
+ j = self.lr0_cidhash.get(id(g),-1) # Go to next state
+
+ # When we get here, j is the final state, now we have to locate the production
+ for r in C[j]:
+ if r.name != p.name: continue
+ if r.len != p.len: continue
+ i = 0
+ # This look is comparing a production ". A B C" with "A B C ."
+ while i < r.lr_index:
+ if r.prod[i] != p.prod[i+1]: break
+ i = i + 1
+ else:
+ lookb.append((j,r))
+ for i in includes:
+ if not i in includedict: includedict[i] = []
+ includedict[i].append((state,N))
+ lookdict[(state,N)] = lookb
- if method == 'LALR':
- add_lalr_lookaheads(C)
+ return lookdict,includedict
+ # -----------------------------------------------------------------------------
+ # compute_read_sets()
+ #
+ # Given a set of LR(0) items, this function computes the read sets.
+ #
+ # Inputs: C = Set of LR(0) items
+ # ntrans = Set of nonterminal transitions
+ # nullable = Set of empty transitions
+ #
+ # Returns a set containing the read sets
+ # -----------------------------------------------------------------------------
+
+ def compute_read_sets(self,C, ntrans, nullable):
+ FP = lambda x: self.dr_relation(C,x,nullable)
+ R = lambda x: self.reads_relation(C,x,nullable)
+ F = digraph(ntrans,R,FP)
+ return F
- # Build the parser table, state by state
- st = 0
- for I in C:
- # Loop over each production in I
- actlist = [ ] # List of actions
- st_action = { }
- st_actionp = { }
- st_goto = { }
- if yaccdebug:
- _vf.write("\nstate %d\n\n" % st)
+ # -----------------------------------------------------------------------------
+ # compute_follow_sets()
+ #
+ # Given a set of LR(0) items, a set of non-terminal transitions, a readset,
+ # and an include set, this function computes the follow sets
+ #
+ # Follow(p,A) = Read(p,A) U U {Follow(p',B) | (p,A) INCLUDES (p',B)}
+ #
+ # Inputs:
+ # ntrans = Set of nonterminal transitions
+ # readsets = Readset (previously computed)
+ # inclsets = Include sets (previously computed)
+ #
+ # Returns a set containing the follow sets
+ # -----------------------------------------------------------------------------
+
+ def compute_follow_sets(self,ntrans,readsets,inclsets):
+ FP = lambda x: readsets[x]
+ R = lambda x: inclsets.get(x,[])
+ F = digraph(ntrans,R,FP)
+ return F
+
+ # -----------------------------------------------------------------------------
+ # add_lookaheads()
+ #
+ # Attaches the lookahead symbols to grammar rules.
+ #
+ # Inputs: lookbacks - Set of lookback relations
+ # followset - Computed follow set
+ #
+ # This function directly attaches the lookaheads to productions contained
+ # in the lookbacks set
+ # -----------------------------------------------------------------------------
+
+ def add_lookaheads(self,lookbacks,followset):
+ for trans,lb in lookbacks.items():
+ # Loop over productions in lookback
+ for state,p in lb:
+ if not state in p.lookaheads:
+ p.lookaheads[state] = []
+ f = followset.get(trans,[])
+ for a in f:
+ if a not in p.lookaheads[state]: p.lookaheads[state].append(a)
+
+ # -----------------------------------------------------------------------------
+ # add_lalr_lookaheads()
+ #
+ # This function does all of the work of adding lookahead information for use
+ # with LALR parsing
+ # -----------------------------------------------------------------------------
+
+ def add_lalr_lookaheads(self,C):
+ # Determine all of the nullable nonterminals
+ nullable = self.compute_nullable_nonterminals()
+
+ # Find all non-terminal transitions
+ trans = self.find_nonterminal_transitions(C)
+
+ # Compute read sets
+ readsets = self.compute_read_sets(C,trans,nullable)
+
+ # Compute lookback/includes relations
+ lookd, included = self.compute_lookback_includes(C,trans,nullable)
+
+ # Compute LALR FOLLOW sets
+ followsets = self.compute_follow_sets(trans,readsets,included)
+
+ # Add all of the lookaheads
+ self.add_lookaheads(lookd,followsets)
+
+ # -----------------------------------------------------------------------------
+ # lr_parse_table()
+ #
+ # This function constructs the parse tables for SLR or LALR
+ # -----------------------------------------------------------------------------
+ def lr_parse_table(self):
+ Productions = self.grammar.Productions
+ Precedence = self.grammar.Precedence
+ goto = self.lr_goto # Goto array
+ action = self.lr_action # Action array
+ log = self.log # Logger for output
+
+ actionp = { } # Action production array (temporary)
+
+ log.info("Parsing method: %s", self.lr_method)
+
+ # Step 1: Construct C = { I0, I1, ... IN}, collection of LR(0) items
+ # This determines the number of states
+
+ C = self.lr0_items()
+
+ if self.lr_method == 'LALR':
+ self.add_lalr_lookaheads(C)
+
+ # Build the parser table, state by state
+ st = 0
+ for I in C:
+ # Loop over each production in I
+ actlist = [ ] # List of actions
+ st_action = { }
+ st_actionp = { }
+ st_goto = { }
+ log.info("")
+ log.info("state %d", st)
+ log.info("")
for p in I:
- _vf.write(" (%d) %s\n" % (p.number, str(p)))
- _vf.write("\n")
+ log.info(" (%d) %s", p.number, str(p))
+ log.info("")
- for p in I:
- try:
- if p.len == p.lr_index + 1:
- if p.name == "S'":
- # Start symbol. Accept!
- st_action["$end"] = 0
- st_actionp["$end"] = p
- else:
- # We are at the end of a production. Reduce!
- if method == 'LALR':
- laheads = p.lookaheads[st]
+ for p in I:
+ if p.len == p.lr_index + 1:
+ if p.name == "S'":
+ # Start symbol. Accept!
+ st_action["$end"] = 0
+ st_actionp["$end"] = p
else:
- laheads = Follow[p.name]
- for a in laheads:
- actlist.append((a,p,"reduce using rule %d (%s)" % (p.number,p)))
- r = st_action.get(a,None)
- if r is not None:
- # Whoa. Have a shift/reduce or reduce/reduce conflict
- if r > 0:
- # Need to decide on shift or reduce here
- # By default we favor shifting. Need to add
- # some precedence rules here.
- sprec,slevel = Productions[st_actionp[a].number].prec
- rprec,rlevel = Precedence.get(a,('right',0))
- if (slevel < rlevel) or ((slevel == rlevel) and (rprec == 'left')):
- # We really need to reduce here.
- st_action[a] = -p.number
- st_actionp[a] = p
- if not slevel and not rlevel:
- _vfc.write("shift/reduce conflict in state %d resolved as reduce.\n" % st)
- _vf.write(" ! shift/reduce conflict for %s resolved as reduce.\n" % a)
- n_srconflict += 1
- elif (slevel == rlevel) and (rprec == 'nonassoc'):
- st_action[a] = None
- else:
- # Hmmm. Guess we'll keep the shift
- if not rlevel:
- _vfc.write("shift/reduce conflict in state %d resolved as shift.\n" % st)
- _vf.write(" ! shift/reduce conflict for %s resolved as shift.\n" % a)
- n_srconflict +=1
- elif r < 0:
- # Reduce/reduce conflict. In this case, we favor the rule
- # that was defined first in the grammar file
- oldp = Productions[-r]
- pp = Productions[p.number]
- if oldp.line > pp.line:
- st_action[a] = -p.number
- st_actionp[a] = p
- # sys.stderr.write("Reduce/reduce conflict in state %d\n" % st)
- n_rrconflict += 1
- _vfc.write("reduce/reduce conflict in state %d resolved using rule %d (%s).\n" % (st, st_actionp[a].number, st_actionp[a]))
- _vf.write(" ! reduce/reduce conflict for %s resolved using rule %d (%s).\n" % (a,st_actionp[a].number, st_actionp[a]))
- else:
- sys.stderr.write("Unknown conflict in state %d\n" % st)
+ # We are at the end of a production. Reduce!
+ if self.lr_method == 'LALR':
+ laheads = p.lookaheads[st]
else:
- st_action[a] = -p.number
- st_actionp[a] = p
- else:
- i = p.lr_index
- a = p.prod[i+1] # Get symbol right after the "."
- if Terminals.has_key(a):
- g = lr0_goto(I,a)
- j = _lr0_cidhash.get(id(g),-1)
- if j >= 0:
- # We are in a shift state
- actlist.append((a,p,"shift and go to state %d" % j))
- r = st_action.get(a,None)
- if r is not None:
- # Whoa have a shift/reduce or shift/shift conflict
- if r > 0:
- if r != j:
- sys.stderr.write("Shift/shift conflict in state %d\n" % st)
- elif r < 0:
- # Do a precedence check.
- # - if precedence of reduce rule is higher, we reduce.
- # - if precedence of reduce is same and left assoc, we reduce.
- # - otherwise we shift
- rprec,rlevel = Productions[st_actionp[a].number].prec
- sprec,slevel = Precedence.get(a,('right',0))
- if (slevel > rlevel) or ((slevel == rlevel) and (rprec == 'right')):
- # We decide to shift here... highest precedence to shift
- st_action[a] = j
- st_actionp[a] = p
- if not rlevel:
- n_srconflict += 1
- _vfc.write("shift/reduce conflict in state %d resolved as shift.\n" % st)
- _vf.write(" ! shift/reduce conflict for %s resolved as shift.\n" % a)
- elif (slevel == rlevel) and (rprec == 'nonassoc'):
- st_action[a] = None
+ laheads = self.grammar.Follow[p.name]
+ for a in laheads:
+ actlist.append((a,p,"reduce using rule %d (%s)" % (p.number,p)))
+ r = st_action.get(a,None)
+ if r is not None:
+ # Whoa. Have a shift/reduce or reduce/reduce conflict
+ if r > 0:
+ # Need to decide on shift or reduce here
+ # By default we favor shifting. Need to add
+ # some precedence rules here.
+ sprec,slevel = Productions[st_actionp[a].number].prec
+ rprec,rlevel = Precedence.get(a,('right',0))
+ if (slevel < rlevel) or ((slevel == rlevel) and (rprec == 'left')):
+ # We really need to reduce here.
+ st_action[a] = -p.number
+ st_actionp[a] = p
+ if not slevel and not rlevel:
+ log.info(" ! shift/reduce conflict for %s resolved as reduce",a)
+ self.sr_conflicts.append((st,a,'reduce'))
+ Productions[p.number].reduced += 1
+ elif (slevel == rlevel) and (rprec == 'nonassoc'):
+ st_action[a] = None
+ else:
+ # Hmmm. Guess we'll keep the shift
+ if not rlevel:
+ log.info(" ! shift/reduce conflict for %s resolved as shift",a)
+ self.sr_conflicts.append((st,a,'shift'))
+ elif r < 0:
+ # Reduce/reduce conflict. In this case, we favor the rule
+ # that was defined first in the grammar file
+ oldp = Productions[-r]
+ pp = Productions[p.number]
+ if oldp.line > pp.line:
+ st_action[a] = -p.number
+ st_actionp[a] = p
+ chosenp,rejectp = pp,oldp
+ Productions[p.number].reduced += 1
+ Productions[oldp.number].reduced -= 1
+ else:
+ chosenp,rejectp = oldp,pp
+ self.rr_conflicts.append((st,chosenp,rejectp))
+ log.info(" ! reduce/reduce conflict for %s resolved using rule %d (%s)", a,st_actionp[a].number, st_actionp[a])
else:
- # Hmmm. Guess we'll keep the reduce
- if not slevel and not rlevel:
- n_srconflict +=1
- _vfc.write("shift/reduce conflict in state %d resolved as reduce.\n" % st)
- _vf.write(" ! shift/reduce conflict for %s resolved as reduce.\n" % a)
+ raise LALRError("Unknown conflict in state %d" % st)
+ else:
+ st_action[a] = -p.number
+ st_actionp[a] = p
+ Productions[p.number].reduced += 1
+ else:
+ i = p.lr_index
+ a = p.prod[i+1] # Get symbol right after the "."
+ if a in self.grammar.Terminals:
+ g = self.lr0_goto(I,a)
+ j = self.lr0_cidhash.get(id(g),-1)
+ if j >= 0:
+ # We are in a shift state
+ actlist.append((a,p,"shift and go to state %d" % j))
+ r = st_action.get(a,None)
+ if r is not None:
+ # Whoa have a shift/reduce or shift/shift conflict
+ if r > 0:
+ if r != j:
+ raise LALRError("Shift/shift conflict in state %d" % st)
+ elif r < 0:
+ # Do a precedence check.
+ # - if precedence of reduce rule is higher, we reduce.
+ # - if precedence of reduce is same and left assoc, we reduce.
+ # - otherwise we shift
+ rprec,rlevel = Productions[st_actionp[a].number].prec
+ sprec,slevel = Precedence.get(a,('right',0))
+ if (slevel > rlevel) or ((slevel == rlevel) and (rprec == 'right')):
+ # We decide to shift here... highest precedence to shift
+ Productions[st_actionp[a].number].reduced -= 1
+ st_action[a] = j
+ st_actionp[a] = p
+ if not rlevel:
+ log.info(" ! shift/reduce conflict for %s resolved as shift",a)
+ self.sr_conflicts.append((st,a,'shift'))
+ elif (slevel == rlevel) and (rprec == 'nonassoc'):
+ st_action[a] = None
+ else:
+ # Hmmm. Guess we'll keep the reduce
+ if not slevel and not rlevel:
+ log.info(" ! shift/reduce conflict for %s resolved as reduce",a)
+ self.sr_conflicts.append((st,a,'reduce'))
+ else:
+ raise LALRError("Unknown conflict in state %d" % st)
else:
- sys.stderr.write("Unknown conflict in state %d\n" % st)
- else:
- st_action[a] = j
- st_actionp[a] = p
+ st_action[a] = j
+ st_actionp[a] = p
- except StandardError,e:
- print sys.exc_info()
- raise YaccError, "Hosed in lr_parse_table"
-
- # Print the actions associated with each terminal
- if yaccdebug:
- _actprint = { }
- for a,p,m in actlist:
- if st_action.has_key(a):
- if p is st_actionp[a]:
- _vf.write(" %-15s %s\n" % (a,m))
- _actprint[(a,m)] = 1
- _vf.write("\n")
- for a,p,m in actlist:
- if st_action.has_key(a):
- if p is not st_actionp[a]:
- if not _actprint.has_key((a,m)):
- _vf.write(" ! %-15s [ %s ]\n" % (a,m))
+ # Print the actions associated with each terminal
+ _actprint = { }
+ for a,p,m in actlist:
+ if a in st_action:
+ if p is st_actionp[a]:
+ log.info(" %-15s %s",a,m)
_actprint[(a,m)] = 1
+ log.info("")
+ # Print the actions that were not used. (debugging)
+ not_used = 0
+ for a,p,m in actlist:
+ if a in st_action:
+ if p is not st_actionp[a]:
+ if not (a,m) in _actprint:
+ log.debug(" ! %-15s [ %s ]",a,m)
+ not_used = 1
+ _actprint[(a,m)] = 1
+ if not_used:
+ log.debug("")
+
+ # Construct the goto table for this state
+
+ nkeys = { }
+ for ii in I:
+ for s in ii.usyms:
+ if s in self.grammar.Nonterminals:
+ nkeys[s] = None
+ for n in nkeys:
+ g = self.lr0_goto(I,n)
+ j = self.lr0_cidhash.get(id(g),-1)
+ if j >= 0:
+ st_goto[n] = j
+ log.info(" %-30s shift and go to state %d",n,j)
+
+ action[st] = st_action
+ actionp[st] = st_actionp
+ goto[st] = st_goto
+ st += 1
- # Construct the goto table for this state
- if yaccdebug:
- _vf.write("\n")
- nkeys = { }
- for ii in I:
- for s in ii.usyms:
- if Nonterminals.has_key(s):
- nkeys[s] = None
- for n in nkeys.keys():
- g = lr0_goto(I,n)
- j = _lr0_cidhash.get(id(g),-1)
- if j >= 0:
- st_goto[n] = j
- if yaccdebug:
- _vf.write(" %-30s shift and go to state %d\n" % (n,j))
-
- action[st] = st_action
- actionp[st] = st_actionp
- goto[st] = st_goto
-
- st += 1
-
- if yaccdebug:
- if n_srconflict == 1:
- sys.stderr.write("yacc: %d shift/reduce conflict\n" % n_srconflict)
- if n_srconflict > 1:
- sys.stderr.write("yacc: %d shift/reduce conflicts\n" % n_srconflict)
- if n_rrconflict == 1:
- sys.stderr.write("yacc: %d reduce/reduce conflict\n" % n_rrconflict)
- if n_rrconflict > 1:
- sys.stderr.write("yacc: %d reduce/reduce conflicts\n" % n_rrconflict)
-
-# -----------------------------------------------------------------------------
-# ==== LR Utility functions ====
-# -----------------------------------------------------------------------------
-# -----------------------------------------------------------------------------
-# _lr_write_tables()
-#
-# This function writes the LR parsing tables to a file
-# -----------------------------------------------------------------------------
-
-def lr_write_tables(modulename=tab_module,outputdir=''):
- if isinstance(modulename, types.ModuleType):
- print >>sys.stderr, "Warning module %s is inconsistent with the grammar (ignored)" % modulename
- return
+ # -----------------------------------------------------------------------------
+ # write()
+ #
+ # This function writes the LR parsing tables to a file
+ # -----------------------------------------------------------------------------
- basemodulename = modulename.split(".")[-1]
- filename = os.path.join(outputdir,basemodulename) + ".py"
- try:
- f = open(filename,"w")
+ def write_table(self,modulename,outputdir='',signature=""):
+ basemodulename = modulename.split(".")[-1]
+ filename = os.path.join(outputdir,basemodulename) + ".py"
+ try:
+ f = open(filename,"w")
- f.write("""
+ f.write("""
# %s
# This file is automatically generated. Do not edit.
+_tabversion = %r
-_lr_method = %s
+_lr_method = %r
-_lr_signature = %s
-""" % (filename, repr(_lr_method), repr(Signature.digest())))
+_lr_signature = %r
+ """ % (filename, __tabversion__, self.lr_method, signature))
- # Change smaller to 0 to go back to original tables
- smaller = 1
+ # Change smaller to 0 to go back to original tables
+ smaller = 1
- # Factor out names to try and make smaller
- if smaller:
- items = { }
-
- for s,nd in _lr_action.items():
- for name,v in nd.items():
- i = items.get(name)
- if not i:
- i = ([],[])
- items[name] = i
- i[0].append(s)
- i[1].append(v)
-
- f.write("\n_lr_action_items = {")
- for k,v in items.items():
- f.write("%r:([" % k)
- for i in v[0]:
- f.write("%r," % i)
- f.write("],[")
- for i in v[1]:
- f.write("%r," % i)
+ # Factor out names to try and make smaller
+ if smaller:
+ items = { }
- f.write("]),")
- f.write("}\n")
+ for s,nd in self.lr_action.items():
+ for name,v in nd.items():
+ i = items.get(name)
+ if not i:
+ i = ([],[])
+ items[name] = i
+ i[0].append(s)
+ i[1].append(v)
+
+ f.write("\n_lr_action_items = {")
+ for k,v in items.items():
+ f.write("%r:([" % k)
+ for i in v[0]:
+ f.write("%r," % i)
+ f.write("],[")
+ for i in v[1]:
+ f.write("%r," % i)
- f.write("""
+ f.write("]),")
+ f.write("}\n")
+
+ f.write("""
_lr_action = { }
for _k, _v in _lr_action_items.items():
for _x,_y in zip(_v[0],_v[1]):
- if not _lr_action.has_key(_x): _lr_action[_x] = { }
+ if not _x in _lr_action: _lr_action[_x] = { }
_lr_action[_x][_k] = _y
del _lr_action_items
""")
- else:
- f.write("\n_lr_action = { ");
- for k,v in _lr_action.items():
- f.write("(%r,%r):%r," % (k[0],k[1],v))
- f.write("}\n");
-
- if smaller:
- # Factor out names to try and make smaller
- items = { }
-
- for s,nd in _lr_goto.items():
- for name,v in nd.items():
- i = items.get(name)
- if not i:
- i = ([],[])
- items[name] = i
- i[0].append(s)
- i[1].append(v)
-
- f.write("\n_lr_goto_items = {")
- for k,v in items.items():
- f.write("%r:([" % k)
- for i in v[0]:
- f.write("%r," % i)
- f.write("],[")
- for i in v[1]:
- f.write("%r," % i)
+ else:
+ f.write("\n_lr_action = { ");
+ for k,v in self.lr_action.items():
+ f.write("(%r,%r):%r," % (k[0],k[1],v))
+ f.write("}\n");
+
+ if smaller:
+ # Factor out names to try and make smaller
+ items = { }
+
+ for s,nd in self.lr_goto.items():
+ for name,v in nd.items():
+ i = items.get(name)
+ if not i:
+ i = ([],[])
+ items[name] = i
+ i[0].append(s)
+ i[1].append(v)
+
+ f.write("\n_lr_goto_items = {")
+ for k,v in items.items():
+ f.write("%r:([" % k)
+ for i in v[0]:
+ f.write("%r," % i)
+ f.write("],[")
+ for i in v[1]:
+ f.write("%r," % i)
- f.write("]),")
- f.write("}\n")
+ f.write("]),")
+ f.write("}\n")
- f.write("""
+ f.write("""
_lr_goto = { }
for _k, _v in _lr_goto_items.items():
for _x,_y in zip(_v[0],_v[1]):
- if not _lr_goto.has_key(_x): _lr_goto[_x] = { }
+ if not _x in _lr_goto: _lr_goto[_x] = { }
_lr_goto[_x][_k] = _y
del _lr_goto_items
""")
- else:
- f.write("\n_lr_goto = { ");
- for k,v in _lr_goto.items():
- f.write("(%r,%r):%r," % (k[0],k[1],v))
- f.write("}\n");
-
- # Write production table
- f.write("_lr_productions = [\n")
- for p in Productions:
- if p:
- if (p.func):
- f.write(" (%r,%d,%r,%r,%d),\n" % (p.name, p.len, p.func.__name__,p.file,p.line))
- else:
- f.write(" (%r,%d,None,None,None),\n" % (p.name, p.len))
else:
- f.write(" None,\n")
- f.write("]\n")
-
- f.close()
-
- except IOError,e:
- print >>sys.stderr, "Unable to create '%s'" % filename
- print >>sys.stderr, e
- return
-
-def lr_read_tables(module=tab_module,optimize=0):
- global _lr_action, _lr_goto, _lr_productions, _lr_method
- try:
- if isinstance(module,types.ModuleType):
- parsetab = module
- else:
- exec "import %s as parsetab" % module
+ f.write("\n_lr_goto = { ");
+ for k,v in self.lr_goto.items():
+ f.write("(%r,%r):%r," % (k[0],k[1],v))
+ f.write("}\n");
+
+ # Write production table
+ f.write("_lr_productions = [\n")
+ for p in self.lr_productions:
+ if p.func:
+ f.write(" (%r,%r,%d,%r,%r,%d),\n" % (p.str,p.name, p.len, p.func,p.file,p.line))
+ else:
+ f.write(" (%r,%r,%d,None,None,None),\n" % (str(p),p.name, p.len))
+ f.write("]\n")
+ f.close()
+
+ except IOError:
+ e = sys.exc_info()[1]
+ sys.stderr.write("Unable to create '%s'\n" % filename)
+ sys.stderr.write(str(e)+"\n")
+ return
- if (optimize) or (Signature.digest() == parsetab._lr_signature):
- _lr_action = parsetab._lr_action
- _lr_goto = parsetab._lr_goto
- _lr_productions = parsetab._lr_productions
- _lr_method = parsetab._lr_method
- return 1
- else:
- return 0
- except (ImportError,AttributeError):
- return 0
+ # -----------------------------------------------------------------------------
+ # pickle_table()
+ #
+ # This function pickles the LR parsing tables to a supplied file object
+ # -----------------------------------------------------------------------------
+ def pickle_table(self,filename,signature=""):
+ try:
+ import cPickle as pickle
+ except ImportError:
+ import pickle
+ outf = open(filename,"wb")
+ pickle.dump(__tabversion__,outf,pickle_protocol)
+ pickle.dump(self.lr_method,outf,pickle_protocol)
+ pickle.dump(signature,outf,pickle_protocol)
+ pickle.dump(self.lr_action,outf,pickle_protocol)
+ pickle.dump(self.lr_goto,outf,pickle_protocol)
+
+ outp = []
+ for p in self.lr_productions:
+ if p.func:
+ outp.append((p.str,p.name, p.len, p.func,p.file,p.line))
+ else:
+ outp.append((str(p),p.name,p.len,None,None,None))
+ pickle.dump(outp,outf,pickle_protocol)
+ outf.close()
# -----------------------------------------------------------------------------
-# yacc(module)
+# === INTROSPECTION ===
#
-# Build the parser module
+# The following functions and classes are used to implement the PLY
+# introspection features followed by the yacc() function itself.
# -----------------------------------------------------------------------------
-def yacc(method=default_lr, debug=yaccdebug, module=None, tabmodule=tab_module, start=None, check_recursion=1, optimize=0,write_tables=1,debugfile=debug_file,outputdir=''):
- global yaccdebug
- yaccdebug = debug
+# -----------------------------------------------------------------------------
+# get_caller_module_dict()
+#
+# This function returns a dictionary containing all of the symbols defined within
+# a caller further down the call stack. This is used to get the environment
+# associated with the yacc() call if none was provided.
+# -----------------------------------------------------------------------------
- initialize_vars()
- files = { }
- error = 0
+def get_caller_module_dict(levels):
+ try:
+ raise RuntimeError
+ except RuntimeError:
+ e,b,t = sys.exc_info()
+ f = t.tb_frame
+ while levels > 0:
+ f = f.f_back
+ levels -= 1
+ ldict = f.f_globals.copy()
+ if f.f_globals != f.f_locals:
+ ldict.update(f.f_locals)
+
+ return ldict
+
+# -----------------------------------------------------------------------------
+# parse_grammar()
+#
+# This takes a raw grammar rule string and parses it into production data
+# -----------------------------------------------------------------------------
+def parse_grammar(doc,file,line):
+ grammar = []
+ # Split the doc string into lines
+ pstrings = doc.splitlines()
+ lastp = None
+ dline = line
+ for ps in pstrings:
+ dline += 1
+ p = ps.split()
+ if not p: continue
+ try:
+ if p[0] == '|':
+ # This is a continuation of a previous rule
+ if not lastp:
+ raise SyntaxError("%s:%d: Misplaced '|'" % (file,dline))
+ prodname = lastp
+ syms = p[1:]
+ else:
+ prodname = p[0]
+ lastp = prodname
+ syms = p[2:]
+ assign = p[1]
+ if assign != ':' and assign != '::=':
+ raise SyntaxError("%s:%d: Syntax error. Expected ':'" % (file,dline))
+
+ grammar.append((file,dline,prodname,syms))
+ except SyntaxError:
+ raise
+ except Exception:
+ raise SyntaxError("%s:%d: Syntax error in rule '%s'" % (file,dline,ps.strip()))
+
+ return grammar
+
+# -----------------------------------------------------------------------------
+# ParserReflect()
+#
+# This class represents information extracted for building a parser including
+# start symbol, error function, tokens, precedence list, action functions,
+# etc.
+# -----------------------------------------------------------------------------
+class ParserReflect(object):
+ def __init__(self,pdict,log=None):
+ self.pdict = pdict
+ self.start = None
+ self.error_func = None
+ self.tokens = None
+ self.files = {}
+ self.grammar = []
+ self.error = 0
+ if log is None:
+ self.log = PlyLogger(sys.stderr)
+ else:
+ self.log = log
- # Add parsing method to signature
- Signature.update(method)
+ # Get all of the basic information
+ def get_all(self):
+ self.get_start()
+ self.get_error_func()
+ self.get_tokens()
+ self.get_precedence()
+ self.get_pfunctions()
+
+ # Validate all of the information
+ def validate_all(self):
+ self.validate_start()
+ self.validate_error_func()
+ self.validate_tokens()
+ self.validate_precedence()
+ self.validate_pfunctions()
+ self.validate_files()
+ return self.error
- # If a "module" parameter was supplied, extract its dictionary.
- # Note: a module may in fact be an instance as well.
+ # Compute a signature over the grammar
+ def signature(self):
+ try:
+ from hashlib import md5
+ except ImportError:
+ from md5 import md5
+ try:
+ sig = md5()
+ if self.start:
+ sig.update(self.start.encode('latin-1'))
+ if self.prec:
+ sig.update("".join(["".join(p) for p in self.prec]).encode('latin-1'))
+ if self.tokens:
+ sig.update(" ".join(self.tokens).encode('latin-1'))
+ for f in self.pfuncs:
+ if f[3]:
+ sig.update(f[3].encode('latin-1'))
+ except (TypeError,ValueError):
+ pass
+ return sig.digest()
- if module:
- # User supplied a module object.
- if isinstance(module, types.ModuleType):
- ldict = module.__dict__
- elif isinstance(module, _INSTANCETYPE):
- _items = [(k,getattr(module,k)) for k in dir(module)]
- ldict = { }
- for i in _items:
- ldict[i[0]] = i[1]
- else:
- raise ValueError,"Expected a module"
+ # -----------------------------------------------------------------------------
+ # validate_file()
+ #
+ # This method checks to see if there are duplicated p_rulename() functions
+ # in the parser module file. Without this function, it is really easy for
+ # users to make mistakes by cutting and pasting code fragments (and it's a real
+ # bugger to try and figure out why the resulting parser doesn't work). Therefore,
+ # we just do a little regular expression pattern matching of def statements
+ # to try and detect duplicates.
+ # -----------------------------------------------------------------------------
+
+ def validate_files(self):
+ # Match def p_funcname(
+ fre = re.compile(r'\s*def\s+(p_[a-zA-Z_0-9]*)\(')
+
+ for filename in self.files.keys():
+ base,ext = os.path.splitext(filename)
+ if ext != '.py': return 1 # No idea. Assume it's okay.
- else:
- # No module given. We might be able to get information from the caller.
- # Throw an exception and unwind the traceback to get the globals
+ try:
+ f = open(filename)
+ lines = f.readlines()
+ f.close()
+ except IOError:
+ continue
- try:
- raise RuntimeError
- except RuntimeError:
- e,b,t = sys.exc_info()
- f = t.tb_frame
- f = f.f_back # Walk out to our calling function
- if f.f_globals is f.f_locals: # Collect global and local variations from caller
- ldict = f.f_globals
- else:
- ldict = f.f_globals.copy()
- ldict.update(f.f_locals)
+ counthash = { }
+ for linen,l in enumerate(lines):
+ linen += 1
+ m = fre.match(l)
+ if m:
+ name = m.group(1)
+ prev = counthash.get(name)
+ if not prev:
+ counthash[name] = linen
+ else:
+ self.log.warning("%s:%d: Function %s redefined. Previously defined on line %d", filename,linen,name,prev)
- # Add starting symbol to signature
- if not start:
- start = ldict.get("start",None)
- if start:
- Signature.update(start)
+ # Get the start symbol
+ def get_start(self):
+ self.start = self.pdict.get('start')
+
+ # Validate the start symbol
+ def validate_start(self):
+ if self.start is not None:
+ if not isinstance(self.start,str):
+ self.log.error("'start' must be a string")
# Look for error handler
- ef = ldict.get('p_error',None)
- if ef:
- if isinstance(ef,types.FunctionType):
- ismethod = 0
- elif isinstance(ef, types.MethodType):
- ismethod = 1
- else:
- raise YaccError,"'p_error' defined, but is not a function or method."
- eline = ef.func_code.co_firstlineno
- efile = ef.func_code.co_filename
- files[efile] = None
-
- if (ef.func_code.co_argcount != 1+ismethod):
- raise YaccError,"%s:%d: p_error() requires 1 argument." % (efile,eline)
- global Errorfunc
- Errorfunc = ef
- else:
- print >>sys.stderr, "yacc: Warning. no p_error() function is defined."
+ def get_error_func(self):
+ self.error_func = self.pdict.get('p_error')
+
+ # Validate the error function
+ def validate_error_func(self):
+ if self.error_func:
+ if isinstance(self.error_func,types.FunctionType):
+ ismethod = 0
+ elif isinstance(self.error_func, types.MethodType):
+ ismethod = 1
+ else:
+ self.log.error("'p_error' defined, but is not a function or method")
+ self.error = 1
+ return
+
+ eline = func_code(self.error_func).co_firstlineno
+ efile = func_code(self.error_func).co_filename
+ self.files[efile] = 1
+
+ if (func_code(self.error_func).co_argcount != 1+ismethod):
+ self.log.error("%s:%d: p_error() requires 1 argument",efile,eline)
+ self.error = 1
+
+ # Get the tokens map
+ def get_tokens(self):
+ tokens = self.pdict.get("tokens",None)
+ if not tokens:
+ self.log.error("No token list is defined")
+ self.error = 1
+ return
+
+ if not isinstance(tokens,(list, tuple)):
+ self.log.error("tokens must be a list or tuple")
+ self.error = 1
+ return
+
+ if not tokens:
+ self.log.error("tokens is empty")
+ self.error = 1
+ return
+
+ self.tokens = tokens
+
+ # Validate the tokens
+ def validate_tokens(self):
+ # Validate the tokens.
+ if 'error' in self.tokens:
+ self.log.error("Illegal token name 'error'. Is a reserved word")
+ self.error = 1
+ return
+
+ terminals = {}
+ for n in self.tokens:
+ if n in terminals:
+ self.log.warning("Token '%s' multiply defined", n)
+ terminals[n] = 1
+
+ # Get the precedence map (if any)
+ def get_precedence(self):
+ self.prec = self.pdict.get("precedence",None)
+
+ # Validate and parse the precedence map
+ def validate_precedence(self):
+ preclist = []
+ if self.prec:
+ if not isinstance(self.prec,(list,tuple)):
+ self.log.error("precedence must be a list or tuple")
+ self.error = 1
+ return
+ for level,p in enumerate(self.prec):
+ if not isinstance(p,(list,tuple)):
+ self.log.error("Bad precedence table")
+ self.error = 1
+ return
- # If running in optimized mode. We're going to read tables instead
+ if len(p) < 2:
+ self.log.error("Malformed precedence entry %s. Must be (assoc, term, ..., term)",p)
+ self.error = 1
+ return
+ assoc = p[0]
+ if not isinstance(assoc,str):
+ self.log.error("precedence associativity must be a string")
+ self.error = 1
+ return
+ for term in p[1:]:
+ if not isinstance(term,str):
+ self.log.error("precedence items must be strings")
+ self.error = 1
+ return
+ preclist.append((term,assoc,level+1))
+ self.preclist = preclist
- if (optimize and lr_read_tables(tabmodule,1)):
- # Read parse table
- del Productions[:]
- for p in _lr_productions:
- if not p:
- Productions.append(None)
+ # Get all p_functions from the grammar
+ def get_pfunctions(self):
+ p_functions = []
+ for name, item in self.pdict.items():
+ if name[:2] != 'p_': continue
+ if name == 'p_error': continue
+ if isinstance(item,(types.FunctionType,types.MethodType)):
+ line = func_code(item).co_firstlineno
+ file = func_code(item).co_filename
+ p_functions.append((line,file,name,item.__doc__))
+
+ # Sort all of the actions by line number
+ p_functions.sort()
+ self.pfuncs = p_functions
+
+
+ # Validate all of the p_functions
+ def validate_pfunctions(self):
+ grammar = []
+ # Check for non-empty symbols
+ if len(self.pfuncs) == 0:
+ self.log.error("no rules of the form p_rulename are defined")
+ self.error = 1
+ return
+
+ for line, file, name, doc in self.pfuncs:
+ func = self.pdict[name]
+ if isinstance(func, types.MethodType):
+ reqargs = 2
+ else:
+ reqargs = 1
+ if func_code(func).co_argcount > reqargs:
+ self.log.error("%s:%d: Rule '%s' has too many arguments",file,line,func.__name__)
+ self.error = 1
+ elif func_code(func).co_argcount < reqargs:
+ self.log.error("%s:%d: Rule '%s' requires an argument",file,line,func.__name__)
+ self.error = 1
+ elif not func.__doc__:
+ self.log.warning("%s:%d: No documentation string specified in function '%s' (ignored)",file,line,func.__name__)
else:
- m = MiniProduction()
- m.name = p[0]
- m.len = p[1]
- m.file = p[3]
- m.line = p[4]
- if p[2]:
- m.func = ldict[p[2]]
- Productions.append(m)
+ try:
+ parsed_g = parse_grammar(doc,file,line)
+ for g in parsed_g:
+ grammar.append((name, g))
+ except SyntaxError:
+ e = sys.exc_info()[1]
+ self.log.error(str(e))
+ self.error = 1
+
+ # Looks like a valid grammar rule
+ # Mark the file in which defined.
+ self.files[file] = 1
+
+ # Secondary validation step that looks for p_ definitions that are not functions
+ # or functions that look like they might be grammar rules.
+
+ for n,v in self.pdict.items():
+ if n[0:2] == 'p_' and isinstance(v, (types.FunctionType, types.MethodType)): continue
+ if n[0:2] == 't_': continue
+ if n[0:2] == 'p_' and n != 'p_error':
+ self.log.warning("'%s' not defined as a function", n)
+ if ((isinstance(v,types.FunctionType) and func_code(v).co_argcount == 1) or
+ (isinstance(v,types.MethodType) and func_code(v).co_argcount == 2)):
+ try:
+ doc = v.__doc__.split(" ")
+ if doc[1] == ':':
+ self.log.warning("%s:%d: Possible grammar rule '%s' defined without p_ prefix",
+ func_code(v).co_filename, func_code(v).co_firstlineno,n)
+ except Exception:
+ pass
- else:
- # Get the tokens map
- if (module and isinstance(module,_INSTANCETYPE)):
- tokens = getattr(module,"tokens",None)
- else:
- tokens = ldict.get("tokens",None)
+ self.grammar = grammar
- if not tokens:
- raise YaccError,"module does not define a list 'tokens'"
- if not (isinstance(tokens,types.ListType) or isinstance(tokens,types.TupleType)):
- raise YaccError,"tokens must be a list or tuple."
-
- # Check to see if a requires dictionary is defined.
- requires = ldict.get("require",None)
- if requires:
- if not (isinstance(requires,types.DictType)):
- raise YaccError,"require must be a dictionary."
+# -----------------------------------------------------------------------------
+# yacc(module)
+#
+# Build a parser
+# -----------------------------------------------------------------------------
- for r,v in requires.items():
- try:
- if not (isinstance(v,types.ListType)):
- raise TypeError
- v1 = [x.split(".") for x in v]
- Requires[r] = v1
- except StandardError:
- print >>sys.stderr, "Invalid specification for rule '%s' in require. Expected a list of strings" % r
-
-
- # Build the dictionary of terminals. We a record a 0 in the
- # dictionary to track whether or not a terminal is actually
- # used in the grammar
-
- if 'error' in tokens:
- print >>sys.stderr, "yacc: Illegal token 'error'. Is a reserved word."
- raise YaccError,"Illegal token name"
-
- for n in tokens:
- if Terminals.has_key(n):
- print >>sys.stderr, "yacc: Warning. Token '%s' multiply defined." % n
- Terminals[n] = [ ]
-
- Terminals['error'] = [ ]
-
- # Get the precedence map (if any)
- prec = ldict.get("precedence",None)
- if prec:
- if not (isinstance(prec,types.ListType) or isinstance(prec,types.TupleType)):
- raise YaccError,"precedence must be a list or tuple."
- add_precedence(prec)
- Signature.update(repr(prec))
-
- for n in tokens:
- if not Precedence.has_key(n):
- Precedence[n] = ('right',0) # Default, right associative, 0 precedence
-
- # Get the list of built-in functions with p_ prefix
- symbols = [ldict[f] for f in ldict.keys()
- if (type(ldict[f]) in (types.FunctionType, types.MethodType) and ldict[f].__name__[:2] == 'p_'
- and ldict[f].__name__ != 'p_error')]
+def yacc(method='LALR', debug=yaccdebug, module=None, tabmodule=tab_module, start=None,
+ check_recursion=1, optimize=0, write_tables=1, debugfile=debug_file,outputdir='',
+ debuglog=None, errorlog = None, picklefile=None):
- # Check for non-empty symbols
- if len(symbols) == 0:
- raise YaccError,"no rules of the form p_rulename are defined."
+ global parse # Reference to the parsing method of the last built parser
- # Sort the symbols by line number
- symbols.sort(lambda x,y: cmp(x.func_code.co_firstlineno,y.func_code.co_firstlineno))
+ # If pickling is enabled, table files are not created
- # Add all of the symbols to the grammar
- for f in symbols:
- if (add_function(f)) < 0:
- error += 1
- else:
- files[f.func_code.co_filename] = None
+ if picklefile:
+ write_tables = 0
- # Make a signature of the docstrings
- for f in symbols:
- if f.__doc__:
- Signature.update(f.__doc__)
+ if errorlog is None:
+ errorlog = PlyLogger(sys.stderr)
- lr_init_vars()
+ # Get the module dictionary used for the parser
+ if module:
+ _items = [(k,getattr(module,k)) for k in dir(module)]
+ pdict = dict(_items)
+ else:
+ pdict = get_caller_module_dict(2)
- if error:
- raise YaccError,"Unable to construct parser."
+ # Collect parser information from the dictionary
+ pinfo = ParserReflect(pdict,log=errorlog)
+ pinfo.get_all()
- if not lr_read_tables(tabmodule):
+ if pinfo.error:
+ raise YaccError("Unable to build parser")
- # Validate files
- for filename in files.keys():
- if not validate_file(filename):
- error = 1
+ # Check signature against table files (if any)
+ signature = pinfo.signature()
- # Validate dictionary
- validate_dict(ldict)
+ # Read the tables
+ try:
+ lr = LRTable()
+ if picklefile:
+ read_signature = lr.read_pickle(picklefile)
+ else:
+ read_signature = lr.read_table(tabmodule)
+ if optimize or (read_signature == signature):
+ try:
+ lr.bind_callables(pinfo.pdict)
+ parser = LRParser(lr,pinfo.error_func)
+ parse = parser.parse
+ return parser
+ except Exception:
+ e = sys.exc_info()[1]
+ errorlog.warning("There was a problem loading the table file: %s", repr(e))
+ except VersionError:
+ e = sys.exc_info()
+ errorlog.warning(str(e))
+ except Exception:
+ pass
+
+ if debuglog is None:
+ if debug:
+ debuglog = PlyLogger(open(debugfile,"w"))
+ else:
+ debuglog = NullLogger()
- if start and not Prodnames.has_key(start):
- raise YaccError,"Bad starting symbol '%s'" % start
+ debuglog.info("Created by PLY version %s (http://www.dabeaz.com/ply)", __version__)
- augment_grammar(start)
- error = verify_productions(cycle_check=check_recursion)
- otherfunc = [ldict[f] for f in ldict.keys()
- if (type(f) in (types.FunctionType,types.MethodType) and ldict[f].__name__[:2] != 'p_')]
- # Check precedence rules
- if check_precedence():
- error = 1
+ errors = 0
- if error:
- raise YaccError,"Unable to construct parser."
+ # Validate the parser information
+ if pinfo.validate_all():
+ raise YaccError("Unable to build parser")
+
+ if not pinfo.error_func:
+ errorlog.warning("no p_error() function is defined")
- build_lritems()
- compute_first1()
- compute_follow(start)
+ # Create a grammar object
+ grammar = Grammar(pinfo.tokens)
- if method in ['SLR','LALR']:
- lr_parse_table(method)
- else:
- raise YaccError, "Unknown parsing method '%s'" % method
+ # Set precedence level for terminals
+ for term, assoc, level in pinfo.preclist:
+ try:
+ grammar.set_precedence(term,assoc,level)
+ except GrammarError:
+ e = sys.exc_info()[1]
+ errorlog.warning("%s",str(e))
+
+ # Add productions to the grammar
+ for funcname, gram in pinfo.grammar:
+ file, line, prodname, syms = gram
+ try:
+ grammar.add_production(prodname,syms,funcname,file,line)
+ except GrammarError:
+ e = sys.exc_info()[1]
+ errorlog.error("%s",str(e))
+ errors = 1
- if write_tables:
- lr_write_tables(tabmodule,outputdir)
+ # Set the grammar start symbols
+ try:
+ if start is None:
+ grammar.set_start(pinfo.start)
+ else:
+ grammar.set_start(start)
+ except GrammarError:
+ e = sys.exc_info()[1]
+ errorlog.error(str(e))
+ errors = 1
+
+ if errors:
+ raise YaccError("Unable to build parser")
+
+ # Verify the grammar structure
+ undefined_symbols = grammar.undefined_symbols()
+ for sym, prod in undefined_symbols:
+ errorlog.error("%s:%d: Symbol '%s' used, but not defined as a token or a rule",prod.file,prod.line,sym)
+ errors = 1
+
+ unused_terminals = grammar.unused_terminals()
+ if unused_terminals:
+ debuglog.info("")
+ debuglog.info("Unused terminals:")
+ debuglog.info("")
+ for term in unused_terminals:
+ errorlog.warning("Token '%s' defined, but not used", term)
+ debuglog.info(" %s", term)
+
+ # Print out all productions to the debug log
+ if debug:
+ debuglog.info("")
+ debuglog.info("Grammar")
+ debuglog.info("")
+ for n,p in enumerate(grammar.Productions):
+ debuglog.info("Rule %-5d %s", n, p)
+
+ # Find unused non-terminals
+ unused_rules = grammar.unused_rules()
+ for prod in unused_rules:
+ errorlog.warning("%s:%d: Rule '%s' defined, but not used", prod.file, prod.line, prod.name)
+
+ if len(unused_terminals) == 1:
+ errorlog.warning("There is 1 unused token")
+ if len(unused_terminals) > 1:
+ errorlog.warning("There are %d unused tokens", len(unused_terminals))
+
+ if len(unused_rules) == 1:
+ errorlog.warning("There is 1 unused rule")
+ if len(unused_rules) > 1:
+ errorlog.warning("There are %d unused rules", len(unused_rules))
+
+ if debug:
+ debuglog.info("")
+ debuglog.info("Terminals, with rules where they appear")
+ debuglog.info("")
+ terms = list(grammar.Terminals)
+ terms.sort()
+ for term in terms:
+ debuglog.info("%-20s : %s", term, " ".join([str(s) for s in grammar.Terminals[term]]))
+
+ debuglog.info("")
+ debuglog.info("Nonterminals, with rules where they appear")
+ debuglog.info("")
+ nonterms = list(grammar.Nonterminals)
+ nonterms.sort()
+ for nonterm in nonterms:
+ debuglog.info("%-20s : %s", nonterm, " ".join([str(s) for s in grammar.Nonterminals[nonterm]]))
+ debuglog.info("")
+
+ if check_recursion:
+ unreachable = grammar.find_unreachable()
+ for u in unreachable:
+ errorlog.warning("Symbol '%s' is unreachable",u)
+
+ infinite = grammar.infinite_cycles()
+ for inf in infinite:
+ errorlog.error("Infinite recursion detected for symbol '%s'", inf)
+ errors = 1
+
+ unused_prec = grammar.unused_precedence()
+ for term, assoc in unused_prec:
+ errorlog.error("Precedence rule '%s' defined for unknown symbol '%s'", assoc, term)
+ errors = 1
- if yaccdebug:
- try:
- f = open(os.path.join(outputdir,debugfile),"w")
- f.write(_vfc.getvalue())
- f.write("\n\n")
- f.write(_vf.getvalue())
- f.close()
- except IOError,e:
- print >>sys.stderr, "yacc: can't create '%s'" % debugfile,e
-
- # Made it here. Create a parser object and set up its internal state.
- # Set global parse() method to bound method of parser object.
-
- p = Parser("xyzzy")
- p.productions = Productions
- p.errorfunc = Errorfunc
- p.action = _lr_action
- p.goto = _lr_goto
- p.method = _lr_method
- p.require = Requires
-
- global parse
- parse = p.parse
-
- global parser
- parser = p
-
- # Clean up all of the globals we created
- if (not optimize):
- yacc_cleanup()
- return p
-
-# yacc_cleanup function. Delete all of the global variables
-# used during table construction
-
-def yacc_cleanup():
- global _lr_action, _lr_goto, _lr_method, _lr_goto_cache
- del _lr_action, _lr_goto, _lr_method, _lr_goto_cache
-
- global Productions, Prodnames, Prodmap, Terminals
- global Nonterminals, First, Follow, Precedence, UsedPrecedence, LRitems
- global Errorfunc, Signature, Requires
-
- del Productions, Prodnames, Prodmap, Terminals
- del Nonterminals, First, Follow, Precedence, UsedPrecedence, LRitems
- del Errorfunc, Signature, Requires
-
- global _vf, _vfc
- del _vf, _vfc
-
-
-# Stub that raises an error if parsing is attempted without first calling yacc()
-def parse(*args,**kwargs):
- raise YaccError, "yacc: No parser built with yacc()"
+ if errors:
+ raise YaccError("Unable to build parser")
+
+ # Run the LRGeneratedTable on the grammar
+ if debug:
+ errorlog.debug("Generating %s tables", method)
+
+ lr = LRGeneratedTable(grammar,method,debuglog)
+
+ if debug:
+ num_sr = len(lr.sr_conflicts)
+
+ # Report shift/reduce and reduce/reduce conflicts
+ if num_sr == 1:
+ errorlog.warning("1 shift/reduce conflict")
+ elif num_sr > 1:
+ errorlog.warning("%d shift/reduce conflicts", num_sr)
+
+ num_rr = len(lr.rr_conflicts)
+ if num_rr == 1:
+ errorlog.warning("1 reduce/reduce conflict")
+ elif num_rr > 1:
+ errorlog.warning("%d reduce/reduce conflicts", num_rr)
+
+ # Write out conflicts to the output file
+ if debug and (lr.sr_conflicts or lr.rr_conflicts):
+ debuglog.warning("")
+ debuglog.warning("Conflicts:")
+ debuglog.warning("")
+
+ for state, tok, resolution in lr.sr_conflicts:
+ debuglog.warning("shift/reduce conflict for %s in state %d resolved as %s", tok, state, resolution)
+
+ already_reported = {}
+ for state, rule, rejected in lr.rr_conflicts:
+ if (state,id(rule),id(rejected)) in already_reported:
+ continue
+ debuglog.warning("reduce/reduce conflict in state %d resolved using rule (%s)", state, rule)
+ debuglog.warning("rejected rule (%s) in state %d", rejected,state)
+ errorlog.warning("reduce/reduce conflict in state %d resolved using rule (%s)", state, rule)
+ errorlog.warning("rejected rule (%s) in state %d", rejected, state)
+ already_reported[state,id(rule),id(rejected)] = 1
+
+ warned_never = []
+ for state, rule, rejected in lr.rr_conflicts:
+ if not rejected.reduced and (rejected not in warned_never):
+ debuglog.warning("Rule (%s) is never reduced", rejected)
+ errorlog.warning("Rule (%s) is never reduced", rejected)
+ warned_never.append(rejected)
+
+ # Write the table file if requested
+ if write_tables:
+ lr.write_table(tabmodule,outputdir,signature)
+
+ # Write a pickled version of the tables
+ if picklefile:
+ lr.pickle_table(picklefile,signature)
+
+ # Build the parser
+ lr.bind_callables(pinfo.pdict)
+ parser = LRParser(lr,pinfo.error_func)
+
+ parse = parser.parse
+ return parser
--------------080004000200030807030507
Content-Type: text/plain;
name="patch-qsgen.py"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
filename="patch-qsgen.py"
--- js/src/xpconnect/src/qsgen.py.orig 2010-04-02 19:02:30.000000000 +0300
+++ js/src/xpconnect/src/qsgen.py 2010-04-07 11:05:56.201435457 +0300
@@ -1,4 +1,4 @@
-#!/usr/bin/env/python
+#!/usr/local/bin/python
# qsgen.py - Generate XPConnect quick stubs.
#
# ***** BEGIN LICENSE BLOCK *****
--------------080004000200030807030507
Content-Type: text/plain;
name="patch-xpidl.py"
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment;
filename="patch-xpidl.py"
--- xpcom/idl-parser/xpidl.py.orig 2010-04-02 19:03:13.000000000 +0300
+++ xpcom/idl-parser/xpidl.py 2010-04-07 11:23:53.544027464 +0300
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/local/bin/python
# xpidl.py - A parser for cross-platform IDL (XPIDL) files.
#
# ***** BEGIN LICENSE BLOCK *****
--------------080004000200030807030507--
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