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Date: Wed, 30 Nov 2011 12:09:01 -0600
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Subject: 5.4's New De-referencing plus assignment
From: ralph@ralphschindler.com (Ralph Schindler)

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Hey all (Filipe),

This was brought up in the thread "New dereferencing syntaxes in 5.4".

I too think this would be beneficial:

   $value = ($obj = new Foo)->produceAValue();

but the current parser (branch 5.4) doesn't have a rule for this.  I've 
attached a quick/working patch, but I don't fully understand the 
ramifications of such a patch.

Can someone explain the drawbacks of increasing the "%expect n" for me?

Would this many s/r require/benefit from a new expression grouping?

More to the point, can we have this small change for 5.4?

Thanks in advance.
-ralph

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diff --git a/Zend/zend_language_parser.y b/Zend/zend_language_parser.y
index a0c671b..f777b36 100644
--- a/Zend/zend_language_parser.y
+++ b/Zend/zend_language_parser.y
@@ -50,7 +50,7 @@ static YYSIZE_T zend_yytnamerr(char*, const char*);
 %}
 
 %pure_parser
-%expect 3
+%expect 4
 
 %token END 0 "end of file"
 %left T_INCLUDE T_INCLUDE_ONCE T_EVAL T_REQUIRE T_REQUIRE_ONCE
@@ -772,6 +772,7 @@ expr_without_variable:
 	|	expr T_INSTANCEOF class_name_reference { zend_do_instanceof(&$$, &$1, &$3, 0 TSRMLS_CC); }
 	|	'(' expr ')' 	{ $$ = $2; }
 	|	new_expr		{ $$ = $1; }
+	|	'(' variable '=' new_expr ')' { zend_check_writable_variable(&$2); zend_do_assign(&$$, &$2, &$4 TSRMLS_CC); } instance_call { $$ = $7; }
 	|	'(' new_expr ')' { $$ = $2; } instance_call { $$ = $5; }
 	|	expr '?' { zend_do_begin_qm_op(&$1, &$2 TSRMLS_CC); }
 		expr ':' { zend_do_qm_true(&$4, &$2, &$5 TSRMLS_CC); }

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