Bug #78434 [Opn]: Generator yields no items after valid() call

Edit report at https://bugs.php.net/bug.php?id=78434&edit=1 ID: 78434 Updated by: nikic@php.net Reported by: enumag at gmail dot com Summary: Generator yields no items after valid() call Status: Open Type: Bug Package: *General Issues Operating System: irrelevant PHP Version: 7.4.0beta2 Block user comment: N Private report: N New Comment: The correct behavior here depends on whether "yield from" is supposed to iterate from the current position of the generator, or from the start (and throw if we're not at the start). To make this more obvious, replace valid() with current() -- should the yield from repeat the value you already fetched? Generally I would agree that it should iterate from the start, in particular because this is what yield from does for non-generator Iterators. Previous Comments: ------------------------------------------------------------------------ [2019-08-21 10:02:01] enumag at gmail dot com Description: ------------ See the example script. The inner $function generator is called twice so two zeros should be yielded from $wrapper. Yet only one is yielded if I call valid() on the Generator before using yield from. Test script: --------------- https://3v4l.org/GfJHG Expected result: ---------------- 00 Actual result: -------------- 0 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=78434&edit=1