Out of nowhere, the tired old dog of PHP compilation rears its ugly head.
Here is an recent e-mail exchange that puts it in its place (along with some information about code browsers and documentors and a lot of confusion on my part). I don’t think anyone is going to mind me posting these since the only one who comes off as an idiot is me.
[Dialog after the jump]
Me, Myself and I
Do you know any good PHP code browser? Like a web page that I can click on a function call it actually jumps to function’s declaration? Also, is there a PHP -> C/C++ codegen/compiler, or any effort on that?
HP,
Happy birthday. I hope all is going well at Facebook. 
The Zend IDE will do click-on-function-code-jump and its quite convenient (I’m told by my devs, I’m old school). It can’t do dynamic function calls or eval()‘d function calls or variable-variables, but for the basics it works fine. I don’t know if Komodo can do this so I’m cc:ing this to the head of ActiveState’s tech support, Jeff Grifiths, so he can answer that. Since I paid for it, I’m sort of interested in the answer myself.
There was effort about three years ago on a PHP->C/C++ extension code generator by a number of developers. I think Marco Tabini of php|architect worked on one, or if not, he knows of who was trying to do this. I added Marco to the cc: so maybe he can provide the status of those things.
There is no C++ codgen. Getting C++ extensions to work in PHP is a chore, IMO. I’d stick with C. I know you love C++, but trust me on this.
This PEAR package is just used to translate a XML definition file into a C extension stubs, not what you are looking for. Probably the authority on this will have to be Sara Golemon who is also on the cc. She has a book called Extending and Embedding PHP which you’ll need to look at. I included her amazon link.
I bet Brian or Lucas has a copy somewhere.
Finally, a word of warning. When this thing was all the rage three years ago, (like a PHP JIT, this sort of stuff tends to go in cycles), I talked with George about this—he’s the guy who co-wrote APC which you use at Facebook. He pointed out that PHP is filled with a lot of edge cases that you won’t think anyone would be stupid enough to exploit until you find out they do. “All APC does” is code cache and yet bugs are still being fixed in it to this day: ask your coworker Brian Shire. A codegen would have to require a “color between the lines” approach to PHP programming in order to actually work, though now with PHP 5 the compatibility set will be much larger.
In general, I’m told Yahoo! maintains around 100+ PHP extensions in their codebase. I’d like to believe that perhaps this has more to do with enabling special bindings with stuff PHP is bad at more than it is for performance to stuff PHP does just fine. I think that every language has a philosophy that it is important to understand because it points to both its strengths and weaknesses. PHP’s philosophies are “shared none” and “glue language” which creates a strength is in its simplicity, flexibility, and scalability, but a glaring weakness in performance and consistency. Codegen is inherently a performance thing which fights against the core nature of PHP. I don’t think its wise to go against the core nature of any language, but as always, I wish you luck, hope to be proven wrong, and am curious to hear what the state is of this.
Jeff Griffiths, ActiveState Komodo
*puts demo-guy hat on*
Komodo IDE 4.0 has ‘go to definition’ as a new feature, so you can select a function and Komodo will go to the function where it is defined, assuming Komodo knows where that is. We’re releasing Komodo 4.0.3 this week which will introduce ‘include everything’ semantics for projects and selected directories, which will greatly improve this kind of feature for people using auto-load mechanisms like Cake or Drupal. Komodo formerly relied on include statements to find stuff.
Marco Tabini, php|architect
My attempt was just a proof-of-concept attempt at demonstrating that it was possible to convert PHP into C (not C++—see below). I (and some others) proved that it was possible, and we left it at that, mostly because we realized that it was pointless—the performance gain of straight PHP->C conversion was not significant enough to justify the loss in maintainability and the potential for incompatibilities between the compiled code and its PHP equivalent.
Nevertheless, there is, however, a (now open-sourced) compiler called Roadsend that claims to be able to compile PHP scripts directly into native binaries on various platforms. I don’t know much about it, but you might want to take a look at it.
There is no C++ codgen. Getting C++ extensions to work in PHP is a chore, IMO. I’d stick with C. I know you love C++, but trust me on this.
That is a very generous assessment of the situation
I am not an expert on internals, but IMHO you’re better off focusing on using PHP as a prototyping environment for those extensions that you eventually want to move to C or C++. A code generator won’t give you that much of a performance boost (because it will still have to deal with PHP’s “magic,” like type juggling) and will introduce all sorts of probable incompatibilities that are bound to come back and bite you eventually.
Plus, don’t forget that Y! counts Rasmus, Andrei and Sara in their ranks—which is enough to hack any part of PHP into submission
Haiping, Facebook
Thanks, Marco. I thought I was just asking Terry some random questions, but then he’s so resourceful, and I got so much helps from experts, and I’m really thankful here.
- For code browser, I kinda want to stay away from any IDEs, just because everyone uses their own way of coding. All I need is a program that I can run to generate static HTML pages linkified by functions and references. Then it would prepare a web site that everyone can jump on to browse codes without any installation of any IDEs. I’m looking into Eclipse, as they have a Java PHP parser and formatter that seems to work for me for this purpose. Is anyone working on that project, or any comments on whether I should go or not go for that? Perhaps there’s some other PHP parser packages that I can use?
- The PHP->C/C++ conversion thing is actually not for performance or any replacement of PHP code we have. I only need it for some simple borrowing of PHP code for I can call them from my C/C++ programs. Embedded PHP has some memory problems, due to our own coding (not PHP itself). But I can read more on that to see if there is a better way. But Marco, is your proof-of-concept coding open sourced? Is it possible for me to have a copy of that? Thanks.
Jeff Grifiths
Ah, ok. “Code Browser” seems to be overloaded. I think you want to look into either doxygen or more likely PHPDocumentor.
Komodo uses a scintilla-related component called silvercity, if you wanted something to call from C++ or Python code.
Haiping
PHPDocumentor doesn’t deal with real coding, does it? It only works on comments, right?
Marco Tabini
…code browser…
Apologies for my abyssal ignorance here, but isn’t that something that phpDoc would be able to do?
…converter code sample…
I would have no problem giving it to you—except it’s long gone 
Have you looked at the source for roadsend? Maybe you can use that as a starting point.
Me
PHPDocumentor tokenizes the source code (I think it uses token_get_all() to do it) when processing. The javadoc comments assist in the documentation (for instance, by declaring type information on the input parameters), but PHPDocumentor will process uncommented code just fine.
