Bug #79614 [Dup]: Nested 'yield from' duplicate first element

Edit report at https://bugs.php.net/bug.php?id=79614&edit=1 ID: 79614 Updated by: requinix@php.net Reported by: ponomarev at gmail dot com Summary: Nested 'yield from' duplicate first element Status: Duplicate Type: Bug Package: Scripting Engine problem PHP Version: 7.4.6 Assigned To: cmb Block user comment: N Private report: N New Comment: Duplicate? 78434 fixed an issue where the first generated item wasn't being yielded. This is an issue where the first generated item is being yielded too many times - and it started after 78434's fix landed in 7.4.6. Previous Comments: ------------------------------------------------------------------------ [2020-05-20 07:17:02] cmb@php.net Well, actually a duplicate of that bug. ------------------------------------------------------------------------ [2020-05-20 02:42:47] requinix@php.net No doubt related to bug #78434. ------------------------------------------------------------------------ [2020-05-20 02:22:18] ponomarev at gmail dot com Description: ------------ See the example script. First element yielded twice if iterate over a generator that yield from another generator. Test script: --------------- https://3v4l.org/2ZQ8d <?php $arr = [1,2,3]; function a($x){ yield from $x; } foreach(a(a($arr)) as $x){ print_r($x); } Expected result: ---------------- 123 Actual result: -------------- 1123 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=79614&edit=1