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Contents | Language Implementations | Plumhead |
These are some ramblings on using ANTLR 3 for Plumhead, or with Parrot in general.
Plumhead.java needs to find the needed classes. This works for me:
export ANTLR_HOME=/home/bernhard/devel/antlr/antlr-3
export PARROT_HOME=/home/bernhard/devel/Parrot/trunk
export CLASSPATH=$ANTLR_HOME/lib/antlr-2.7.7.jar:\
$ANTLR_HOME/lib/antlr-3.0.1.jar:\
$ANTLR_HOME:/lib/antlr-runtime-3.0.1.jar:\
$ANTLR_HOME/lib/stringtemplate-3.1b1.jar:\
$PARROT_HOME/languages/plumhead/src/antlr3:\
$PARROT_HOME/languages/plumhead
Now try: cd languages/plumhead make maintain-antlr3 make build-antlr3 make test-antlr3
Lexer, Parser and TreeParser are in the same file, speak grammar. C and C++ style comments are accepted.
'+' is one or many
'( )' is for grouping '|' as for alternation "''" Sring delimeter, honoring '\t', '\n', '\r'
'{ }' are actions ';' delimits rules 'grammar <name>', set name of Parser, Name of autogenerated Lexer is generated from it
Tell to generate an AST and set lookahead options { output=AST; ASTLabelType=CommonTree; k = 2; }
'Sigil $' is for referencing alternations in actions, Lexer items only ???, also for setting returns
'->' Is for tree construction '^^' Makes a mother '^' Is for matching of tree nodes '[]' declaration and passing of parameters
@members declare additional member variables in the parser class
@init ??
scope a stack for symbols
{ $channel = HIDDEN; } put match into Nirwana
The lexer specification can be in the parser specification. A lexer grammar is automatically generated. 'protected' is gone.
Bernhard Schmalhofer - <Bernhard.Schmalhofer@gmx.de>
L<http://www.antlr.org/>
L<http://www.antlr.org/v3/index.html>
L<http://www.antlr.org/wiki/display/ANTLR3/Welcome+to+ANTLR+V3>
L<http://www.antlr.org:8080/pipermail/antlr-dev/>
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