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Date: Tue, 23 Feb 2010 22:56:21 -0800
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Subject: Re: [PHP-DEV] On closures and lamdba
From: stas@zend.com (Stanislav Malyshev)

Hi!

> Correct me if I'm wrong, but given the fact that PHP only* supports
> functions defined in the global space**, with the additional ability to
> import global variables using the global statement, wouldn't that make
> named functions able to close-over global variables?

It's different mechanism. Globals are just references to variables in 
same global scope, they are not bound to any function, etc.

> And, if the above is true, wouldn't it be consistent to support the use
> statement on named functions, and then deprecate the global statement?

That's why I'm not a big fan of that "consistency" argument here on the 
list - because it usually means "let's implement some feature because I 
like it", but not more. Which is fine, but it has nothing to do with 
consistency.
Particularly, scope capturing and all that has very little relation to 
what globals do. Closures carry around "captured" variables. Regular 
functions don't. Global scope exists independently of them.
The mechanism is similar (well, it's the same engine, how many there can 
be? :) but they are not the same.

> ** namespaced functions don't make any difference, as variables aren't
> namespaced.

I'm not sure what you mean here, as variables in PHP are scoped. Global 
functions are not scoped, of course, but can be namespaced.
-- 
Stanislav Malyshev, Zend Software Architect
stas@zend.com   http://www.zend.com/
(408)253-8829   MSN: stas@zend.com