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







grammar::me::util - AST utilities








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?












This package provides a number of utility command for the
    conversion between the various representations of abstract syntax trees as
    specified 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.







  

  
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.

  

  
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.










This document, and the package it describes, will undoubtedly
    contain bugs and other problems. Please report such in the category
    grammar_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.








abstract syntax tree, syntax tree, tree








Grammars and finite automata








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








  

    0.1
    grammar_me