The Function Type
-----------------

   For readabilty, we declare a new type of object, called "Function".
A `Function' is a C function which returns an `int'.  The type
declaration for `Function' is:

`typedef int Function ();'

   The reason for declaring this new type is to make it easier to write
code describing pointers to C functions.  Let us say we had a variable
called FUNC which was a pointer to a function.  Instead of the classic
C declaration

   `int (*)()func;'

we may write

   `Function *func;'

Similarly, there are

     typedef void VFunction ();
     typedef char *CPFunction (); and
     typedef char **CPPFunction ();

for functions returning no value, `pointer to char', and `pointer to
pointer to char', respectively.