Hi Flavius! I am working on PHP Parser in user land code (https://github.com/nikic/PHP-Parser), which currently has capabilities to parse PHP 5.3 into an AST and compile the nodes back to PHP source.
>From my experience in building it, some notes: First, you seem to try to lex the PHP code yourself too. Why don't you use PHP's internal lexing capabilities? (Like token_get_all does.) PHP is a hard to lex language (with all it's special encapsed string and heredoc syntaxes) and PHP's own lexer (http://lxr.php.net/xref/PHP_TRUNK/Zend/zend_language_scanner.l) is something like two and a half thousand lines long. Second, you seem to try to parse PHP using your own grammar. From my experience, the PHP grammar (http://lxr.php.net/xref/PHP_TRUNK/Zend/zend_language_parser.y) is really messed up and it's already quite hard to strictly adhere to that grammar (as it has lots of strange quirks) and make it AST-able. If you write up your own grammar I doubt that it will ever match the PHP grammar. I think you should stick as much as possible to the PHP grammar and only introduce changes where required. (The grammar I use (https://github.com/nikic/PHP-Parser/blob/master/grammar/zend_language_parser.phpy) is already made AST-able, though some quirks in the language required me to do brain-transplantation at one point.) For example you already have at least one error in the little grammar you have: The opening and closing tags should be filtered away before being passed to the parser as the may occur anywhere, even in the middle of an expression (`echo $hi . ?><?php $hi;` is valid). On Sat, Sep 3, 2011 at 11:21 PM, Flavius Aspra <flavius...@gmail.com> wrote: > Hi > > I'm Flavius Aspra and over the past weeks [1] I've worked on a small > extension, which I think it has a lot of potential. Thanks to everyone > for being patient with me on #php.pecl during this time - I've learned a > lot! > > Meta will enable userland scripts to get the AST of a PHP source code, > to manipulate it, and if desired, to serialize it back to valid PHP code. > > The current status is "not really usable", but it has already reached > around 2k LOCs and I think it's easier for you to review it now, than later. > > The code is still hosted on github, please let me know what needs to be > done to make it PECL-compatible. Advices, bug fixes and improvements are > welcome. Pending TODOs are listed inline, in the code, as they fit, and > longer-term TODOs are in TODO.txt. > > I've already asked for a first thought on IRC, and people seem to see > the need for this extension. > > The project's page is at [2], it's called "phpmeta" there, so no > confusion arises. The extension is simply called "meta". Many other > details can be found in the README. Feel free to ask me anything. > > [1] Actually, I wanted to work on this for GSoC, but I was a little bit > late, so I've worked on it in my spare time > [2] https://github.com/OriginalCopy/phpmeta > > Cheers, > Flavius -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: http://www.php.net/unsub.php
