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y2l(1)			     General Commands Manual			  y2l(1)

NAME
     y2l - Yacc to LaTeX grammar pretty printer

SYNOPSIS
     y2l [-- options] file
     Options:
     [-d] [-h] [-O] [-O{0,1,2}] [-p] [-t{regexp,file}] [-v]

DESCRIPTION
     This utility takes a yacc(1) grammar description file and generates an EBNF
     (Extended	Backus-Naur  Form) grammar from it.  By default, the output will
     be a LaTeX(1) longtable environment, that can be \input{}	into  any  LaTeX
     document.	 Automatic  substitution of symbolic terminals can also be taken
     care of.  Options control whether any optimization should be  done  on  the
     grammar, and whether plain ASCII output should be generated instead.

OPTIONS
     -d     Write out debugging information to standard error.

     -h     Display a short usage summary on standard output and exit.

     -O     Optimize  the  yacc  grammar.  This basic optimization will look for
	    empty rules to make non-terminals  optional.   It  also  recursively
	    generates  choice  groups  and optional groups and elements based on
	    common prefix and suffix token lists.

     -O0    Turn off optimization.

     -O1    This gives the same optimization as the regular -O option.

     -O2    Do basic optimization.  In addition, multiple  rules  for  the  same
	    non-terminal  are combined as a choice group.  Rules that were opti-
	    mized by the first phase as  optional  non-terminals  are  converted
	    into repetitive rules if possible.

     -p     Generate plain ASCII output rather than LaTeX output.

     -tregexp
	    Use  the provided regular expression to determine whether a terminal
	    is a lexical token rather than a literal.  This is useful for  gram-
	    mars where literal tokens represent string literals that differ only
	    in that the string literals are all lowercase versions of the token.
	    Since this is a fairly common practise in yacc grammars, this option
	    ha sbeen provided.

     -tfile
	    Use  the  provided	file as a mapping between literal tokens and the
	    literal strings they represent.  Each line in the file  should  con-
	    tain  two  identifiers:  the first one is the lexical token, and the
	    second one is the literal string it represents.

     -v     Display the program version information on standard error  prior  to
	    doing any processing.

BUGS
     While  no	known bugs seem to exist, there are probably quite a few unknown
     bugs.

AUTHOR
     Kris Van Hees <aedil@alchar.org>

ASI				Aedil's Utilities			  y2l(1)

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