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Date: Thu, 26 Jun 2008 23:07:57 +0200
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To: Alexander Wagner <waqner@gmx.net>
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 Andi Gutmans <andi@zend.com>,
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Subject: Re: [PHP-DEV] [PATCH] [RFC] Closures and lambda functions in PHP
From: chris_se@gmx.net (Christian Seiler)

Hi!

> I see exactly one problem with the patch, which is that the above script 
> shouldn't work without "use (&$i)".
> I find it counterintuitive that the creation of the lambda creates a copy of 
> $i, but all invocations of $lambda use a reference to the same $i.
> For n calls to $lambda, there are only 2 copies of $i (one global, one static 
> in $lambda) where I would expect n+1 copies.

Yes, you're right. My solution for this would be:

-------------- zend_compile.h -------------------------
-void zend_do_fetch_static_variable(znode *varname, znode 
*static_assignment, int fetch_type TSRMLS_DC);
+void zend_do_fetch_static_variable(znode *varname, znode 
*static_assignment, int fetch_type, int as_ref TSRMLS_DC);
-------------- zend_compile.h -------------------------

-------------- zend_compile.c -------------------------
# in zend_do_fetch_lexical_variable:
-zend_do_fetch_static_variable(varname, &value, ZEND_FETCH_STATIC 
TSRMLS_CC);
+zend_do_fetch_static_variable(varname, &value, ZEND_FETCH_STATIC, 
is_ref TSRMLS_CC);

...
-void zend_do_fetch_static_variable(znode *varname, znode 
*static_assignment, int fetch_type TSRMLS_DC)
+void zend_do_fetch_static_variable(znode *varname, znode 
*static_assignment, int fetch_type, int as_ref TSRMLS_DC)
...
-	zend_do_assign_ref(NULL, &lval, &result TSRMLS_CC);
+	if (as_ref) {
+		zend_do_assign_ref(NULL, &lval, &result TSRMLS_CC);
+	} else {
+		zend_do_assign(NULL, &lval, &result TSRMLS_CC);
+	}

# and make sure zend_do_assign can live with NULL for first param
-------------- zend_compile.c -------------------------

-------------- zend_language_parser.y -------------------------
static_var_list:
-		static_var_list ',' T_VARIABLE { zend_do_fetch_static_variable(&$3, 
NULL, ZEND_FETCH_STATIC TSRMLS_CC); }
-	|	static_var_list ',' T_VARIABLE '=' static_scalar { 
zend_do_fetch_static_variable(&$3, &$5, ZEND_FETCH_STATIC TSRMLS_CC); }
-	|	T_VARIABLE  { zend_do_fetch_static_variable(&$1, NULL, 
ZEND_FETCH_STATIC TSRMLS_CC); }
-	|	T_VARIABLE '=' static_scalar { zend_do_fetch_static_variable(&$1, 
&$3, ZEND_FETCH_STATIC TSRMLS_CC); }
+		static_var_list ',' T_VARIABLE { zend_do_fetch_static_variable(&$3, 
NULL, ZEND_FETCH_STATIC, 1 TSRMLS_CC); }
+	|	static_var_list ',' T_VARIABLE '=' static_scalar { 
zend_do_fetch_static_variable(&$3, &$5, ZEND_FETCH_STATIC, 1 TSRMLS_CC); }
+	|	T_VARIABLE  { zend_do_fetch_static_variable(&$1, NULL, 
ZEND_FETCH_STATIC, 1 TSRMLS_CC); }
+	|	T_VARIABLE '=' static_scalar { zend_do_fetch_static_variable(&$1, 
&$3, ZEND_FETCH_STATIC, 1 TSRMLS_CC); }

;
-------------- zend_language_parser.y -------------------------

Any objections (in case copies are wanted at all)?

Regards,
Christian