Hey Christian,

Nice job!

More below:


>  -----Original Message-----

>  From: Christian Seiler [mailto:chris_se@[...].net]

>  Sent: Thursday, June 26, 2008 9:24 AM

>  To: Dmitry Stogov

>  Cc: php-dev List; Andi Gutmans; Stas Malyshev

>  Subject: Re: [PHP-DEV] [PATCH] [RFC] Closures and lambda functions in PHP

>  

-snip-
>  

>    * Lexical vars are now copied instead of referenced by default. Using

>      & in front of the var, the behaviour may be changed. I added that in

>      order to demonstrate that both was possible and that a simply change

>      of grammar suffices. In my eyes this is the main issue where a

>      discussion has to take place (i.e. copy or reference by default?

>      possibility to change default via syntax? which lexical syntax?)

>      before the proposal can be accepted.


I think doing this mixed approach is the right one, i.e. $var1, &$var2. It delivers choice a
nd adds clarity as it's explicit about value vs. reference.


>    * I provided patches for both lexical $var and use ($var) syntaxes.


I lean towards the use(...) syntax.

>    * I provided a patch variant that only stores $this if $this is

>      explicitely used inside a closure (or a nested closure of that

>      closure). This works since it is possible to detect whether $this

>      is used at compile time. For this, I have added a this_used flag

>      to the op_array structure.


Safest not to take shortcuts. You get yourself into trouble with things which will stop work
ing. -1 on this optimization.
 
>    * I added tests (Zend/tests/closures_*.phpt) that ensure the correct

>      behaviour of closures.


Excellent.

>  Anyway, feel free to discuss.

>  

>  In my eyes, the following questions should be answered:

>  

>    * Do you want closures in PHP?


I think most people here feel it's useful or are at least indifferent.

>    * Do you want closures in PHP 5.3?


I really think we need to get the release process for 5.3 going so I suggest to do it for th
e following minor version and commit it to PHP 6.

Andi