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Subject: Re: [PHP-DEV] [RFC] Closures, Lambdas and use
From: stas@zend.com (Stanislav Malyshev)

Hi!

> We have the same with global and static. Can you write them in the middle
> of a funciton/method? So asking for what the consequence is, is irrelevant

Yes you can. Example:

<?php
$a = 1;
function foo()
{
  $a = 2;
  echo $a;
  global $a;
  echo $a;
}
foo();


> that it would break most PHP applications out there. Next, we chose 'use'
> for the keyword, knowing that it was already used elsewhere, dciding that
> it is the lesser evil opposed to creating yet another keyword with all
> implications of that. So this part is irrelevant to my point as well.

You are trying to make it greater evil that it would be otherwise, by 
making syntax that does different things look exactly the same.

> In fact 'use' means create a static variable from the surrounding context,

If you ignore the referencing semantics. Which you should not.

> And to answer the other question. Obviously 'sttaic' and 'use' are executed
> at compile time, so whereever you place them, they are executed before

Actually, static is a runtime construct - it generates FETCH_W opcode 
and ASSIGN_REF opcode.

> So here consistency means placing a syntactical element at the same
> syntactical location related syntactical elements are placed.

The problem is that location is different (you can put static in the 
middle of the code, and you can't put use there) and semantics is 
different (static $a is by ref, use $a is not). Only thing similar is 
that you work with variables in both cases. But if you compare to 
function parameters, semantic is identical - it happens when entering a 
function, it is specified at the start, it can be by-val or by ref. The 
fact that inside engine it is implemented by reusing static's code is 
not reason enough to expose the user to it.
-- 
Stanislav Malyshev, Zend Software Architect
stas@zend.com   http://www.zend.com/
(408)253-8829   MSN: stas@zend.com