grammar::me::util(n)					   Grammar operations and usage 				      grammar::me::util(n)

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NAME

       grammar::me::util - AST utilities

SYNOPSIS

       package require Tcl  8.4

       package require grammar::me::util  ?0.1?

       ::grammar::me::util::ast2tree ast tree ?root?

       ::grammar::me::util::ast2etree ast mcmd tree ?root?

       mcmd lc location

       mcmd tok from ?to?

       ::grammar::me::util::tree2ast tree ?root?

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DESCRIPTION

       This package provides a number of utility command for the conversion between the various representations of abstract syntax trees as speci-
       fied in the document grammar::me_ast.

       ::grammar::me::util::ast2tree ast tree ?root?
	      This command converts an ast from value to object representation. All nodes in the ast will be converted into nodes  of  this  tree,
	      with  the  root of the AST a child of the node root. If this node is not explicitly specified the root of the tree is used. Existing
	      content of tree is not touched, i.e.  neither removed nor changed, with the exception of the specified root node, which will gain  a
	      new child.

       ::grammar::me::util::ast2etree ast mcmd tree ?root?
	      This  command  is  like  ::grammar::me::util::ast2tree, except that the result is in the extended object representation of the input
	      AST.  The source of the extended information is the command prefix mcmd.	It has to understand two methods, lc, and  tok,  with  the
	      semantics specified below.

	      mcmd lc location
		     Takes  the location of a token given as offset in the input stream and return a 2-element list containing the associated line
		     number and column index, in this order.

	      mcmd tok from ?to?
		     Takes one or two locations from and to as offset in the input stream and returns a Tcl list containing the specified part	of
		     the input stream. Both location are inclusive. If to is not specified it will default to the value of from.

		     Each  element  of the returned list is a list containing the token, its associated lexeme, the line number, and column index,
		     in this order.

       Both the ensemble command ::grammar::me::tcl provided by the package grammar::me::tcl and  the  objects	command  created  by  the  package
       ::grammar::me::cpu fit the above specification.

       ::grammar::me::util::tree2ast tree ?root?
	      This  command  converts an ast in (extended) object representation into a value and returns it.  If a root node is specified the AST
	      is generated from that node downward. Otherwise the root of the tree object is used as the starting point.

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will undoubtedly contain bugs and other problems.  Please report such in  the  category  gram-
       mar_me  of  the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883].  Please also report any ideas for enhancements you may
       have for either package and/or documentation.

KEYWORDS

       abstract syntax tree, syntax tree, tree

CATEGORY

       Grammars and finite automata

COPYRIGHT

       Copyright (c) 2005 Andreas Kupries <andreas_kupries@users.sourceforge.net>

grammar_me								0.1						      grammar::me::util(n)