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--- rfc:generator-return-expressions [2015/03/09 15:49] – rewording rdlowrey
+++ rfc:generator-return-expressions [2015/03/09 16:23] – formatting rdlowrey
@@ Line 2: / Line 2: @@
   * Version: 0.1
   * Date: 2015-02-18
-  * Authors: Daniel Lowrey <rdlowrey@php.net>
+  * Author: Daniel Lowrey <rdlowrey@php.net>
   * Contributors: Nikita Popov <nikic@php.net>
   * Status: Under Discussion
@@ Line 170: / Line 170: @@
     return $bar + 42; // unambiguous execution "result"
 };
+?>
 </code>
+===== Reference Returns =====
+Generators currently utilize the `&` operator to indicate values will be yielded by-reference:
+<code php>
+<?php
+function &gen_reference() {
+    $value = 3;
+    while ($value > 0) {
+        yield $value;
+    }
+}
+foreach (gen_reference() as &$number) {
+    echo (--$number).'... ';
+}
+?>
+</code>
+As ''function&'' is already in place to modify yield values we have no way to differentiate between by-reference yield values and by-reference return values. While it would be possible to use ''function&'' to mark returns as by-reference, this proposal's position is that no correlation exists between the "reference-ness" of yielded values and return values. Instead of introducing new tokens or syntax to allow by-reference returns this proposal //always// uses ''ZVAL_COPY'' on return zvals. In short: by-reference returns are not supported in generator return expressions.