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y2l(1)			    General Commands Manual			y2l(1)

       y2l - Yacc to LaTeX grammar pretty printer

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

       This  utility takes a yacc(1) grammar description file and generates an
       EBNF (Extended Backus-Naur Form)	grammar	from it.  By default, the out-
       put 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	gener-
       ated instead.

       -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	recur-
	      sively  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
	      optimized	by the first phase as optional non-terminals are  con-
	      verted into repetitive rules if possible.

       -p     Generate plain ASCII output rather than LaTeX output.

	      Use  the provided	regular	expression to determine	whether	a ter-
	      minal is a lexical token rather than a literal.  This is	useful
	      for grammars where literal tokens	represent string literals that
	      differ only in that the string literals are all  lowercase  ver-
	      sions  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 contain two identifiers: the first	one is the lexical to-
	      ken, and the second one is the literal string it represents.

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

       While no	known bugs seem	to exist, there	are probably quite a  few  un-
       known bugs.

       Kris Van	Hees <>

ASI			       Aedil's Utilities			y2l(1)


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