NAME

       pyacc - Pascal Yacc compiler compiler.

USAGE

       yacc [options] yacc-file[.y] [output-file[.pas]]

       SH OPTIONS

       -v     Verbose:  Pascal  Yacc  generates  a  readable description of the generated parser,
              written to yacc-file with new extension .lst.

       -d     Debug: TP Yacc generates a parser with debugging output.

DESCRIPTION

       TP Yacc is a program that lets you prepare parsers from the description of input languages
       by  BNF-like  grammars. You simply specify the grammar for your target language, augmented
       with the Turbo Pascal code necessary to process the  syntactic  constructs,  and  TP  Yacc
       translates  your  grammar into the Turbo Pascal code for a corresponding parser subroutine
       named yyparse.

       TP Yacc parses the source grammar contained in yacc-file  (with  default  suffix  .y)  and
       writes the constructed parser subroutine to the specified output-file (with default suffix
       .pas); if no output file is specified, output goes to yacc-file with new suffix  .pas.  If
       any  errors  are  found  during  compilation,  error messages are written to the list file
       (yacc-file with new suffix .lst).

       The generated parser routine, yyparse, is declared as:

          function yyparse : Integer;

       This routine may be called by your main program to execute the parser.  The  return  value
       of the yyparse routine denotes success or failure of the parser (possible return values: 0
       = success, 1 = unrecoverable syntax error or parse stack overflow).

       Similar to TP Lex, the code  template  for  the  yyparse  routine  may  be  found  in  the
       yyparse.cod  file.  The rules for locating this file are analogous to those of TP Lex (see
       Section `TP Lex').

       The TP Yacc library (YaccLib) unit is required by programs using Yacc- generated  parsers;
       you  will  therefore have to put an appropriate uses clause into your program or unit that
       contains the parser routine. The YaccLib unit also provides some  routines  which  may  be
       used  to  control  the  actions  of  the  parser.  See  the  file  yacclib.pas for further
       information.

More information

       For more information, see the documentation that comes with TP lex and yacc.

AUTHOR

       Albert Graeff (<ag@muwiinfa.geschichte.uni-mainz.de>, <Dr.Graef@t-online.de>)

SEE ALSO

       ppc386(1) plex(1)