README.md
What do all those files mean?
php5.y
: PHP 5 grammar written in a pseudo languagephp7.y
: PHP 7 grammar written in a pseudo languagetokens.y
: Tokens definition shared between PHP 5 and PHP 7 grammarsparser.template
: Akmyacc
parser prototype file for PHPtokens.template
: Akmyacc
prototype file for theTokens
classrebuildParsers.php
: Preprocesses the grammar and builds the parser usingkmyacc
.phpy pseudo language
The .y
file is a normal grammer in kmyacc
(yacc
) style, with some transformations
applied to it:
- Nodes are created using the syntax
Name[..., ...]
. This is transformed intonew Name(..., ..., attributes())
- Some function-like constructs are resolved (see
rebuildParsers.php
for a list)
Building the parser
In order to rebuild the parser, you need moriyoshi’s fork of kmyacc.
After you compiled/installed it, run the rebuildParsers.php
script.
By default only the Parser.php
is built. If you want to additionally emit debug symbols and create y.output
, run the
script with --debug
. If you want to retain the preprocessed grammar pass --keep-tmp-grammar
.