grammar::me::util(3tcl) Grammar operations and usage grammar::me::util(3tcl)
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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 representa-
tion. 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 pre-
fix 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 in-
put stream and return a 2-element list containing the as-
sociated 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 speci-
fied part of the input stream. Both location are inclu-
sive. 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 ::gram-
mar::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 grammar_me
of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please
also report any ideas for enhancements you may have for either package
and/or documentation.
When proposing code changes, please provide unified diffs, i.e the out-
put of diff -u.
Note further that attachments are strongly preferred over inlined
patches. Attachments can be made by going to the Edit form of the
ticket immediately after its creation, and then using the left-most
button in the secondary navigation bar.
KEYWORDS
abstract syntax tree, syntax tree, tree
CATEGORY
Grammars and finite automata
COPYRIGHT
Copyright (c) 2005 Andreas Kupries <andreas_kupries@users.sourceforge.net>
tcllib 0.1 grammar::me::util(3tcl)