yapp - A perl frontend to the Parse::Yapp module


yapp [options] grammar[.yp]

yapp -V

yapp -h


yapp is a frontend to the Parse::Yapp module, which lets you compile Parse::Yapp grammar input files into Perl LALR(1) OO parser modules.


Options, as of today, are all optionals :-)

Creates a file grammar.output describing your parser. It will show you a summary of conflicts, rules, the DFA (Deterministic Finite Automaton) states and overall usage of the parser.
Create a standalone module in which the driver is included. Note that if you have more than one parser module called from a program, to have it standalone, you need this option only for one of your parser module.
Disable source file line numbering embedded in your parser module. I don't know why one should need it, but it's there.
-m module
Gives your parser module the package name (or name space or module name or class name or whatever-you-call-it) of module. It defaults to grammar
-o outfile
The compiled output file will be named outfile for your parser module. It defaults to or, if you specified the option -m A::Module::Name (see below), to
-t filename
The -t filename option allows you to specify a file which should be used as template for generating the parser output. The default is to use the internal template defined in For how to write your own template and which substitutions are available, have a look to the module : it should be obvious.
-b shebang

If you work on systems that understand so called shebangs, and your generated parser is directly an executable script, you can specifie one with the -b option, ie:

    yapp \-b '/usr/local/bin/perl \-w' \-o myscript.yp

This will output a file called whose very first line is:

    #!/usr/local/bin/perl \-w

The argument is mandatory, but if you specify an empty string, the value of $Config{perlpath} will be used instead.

The input grammar file. If no suffix is given, and the file does not exists, an attempt to open the file with a suffix of .yp is tried before exiting.
Display current version of Parse::Yapp and gracefully exits.
Display the usage screen.


None known now :-)


Francois Desarmenien <>


(c) Copyright 1998-1999 Francois Desarmenien, all rights reserved. See Parse::Yapp(3) for legal use and distribution rights


Parse::Yapp(3) Perl(1) yacc(1) bison(1)