PHP language specification?

Question

I know there is an official document for Java (JLS), I'd like to know if it's also the case of PHP language. I found the "Language Reference" section on the PHP manual, but it doesn't look as detailed as the JLS.

The thing is I have a good practical knowledge of PHP but I'm miserably clueless about what really happens under the hood.

If there isn't any official document, could you recommend me some good books to read?

Answer 1

An initial draft specification for the PHP language has now been announced. The introduction of the specification reads as follows:

This specification is intended to provide a complete and concise definition of the syntax and semantics of the PHP language, suitable for use by the following:

• Implementers of a PHP compiler
• Implementers of a test suite for the PHP language
• Programmers writing PHP code

For now, the runtime library has been excluded, as that is documented at www.php.net. As such, all forward references to library facilities have placeholders of the form (§xx).

See also the latest version of the draft.

Answer 2

There was a discussion about that topic on the internals mailing list not too long ago.

You can check the status there.

Starting Post: http://marc.info/?l=php-internals&m=129379585417113&w=2

Dear internals

After enviously looking at pythons grammar (http://docs.python.org/dev/reference/grammar.html) I keep feeling that PHP is missing out on a lot of interesting meta projects by not having an official EBNF. [...]

and one hopefully helpfull follow up describing some grammar:

http://marc.info/?l=php-internals&m=129387252319019&w=2

And Stats take in the matter:

http://marc.info/?l=php-internals&m=129383062812273&w=2

Hi! [...]

You're not the only one thinking about it. But so far nobody moved from thinking about it to actually doing it :)

-- Stanislav Malyshev, Software Architect