Req #80735 [Fbk->Opn]: yield break
Edit report at https://bugs.php.net/bug.php?id=80735&edit=1
ID: 80735
User updated by: petr dot vejchoda at seznam dot cz
Reported by: petr dot vejchoda at seznam dot cz
Summary: yield break
-Status: Feedback
+Status: Open
Type: Feature/Change Request
Package: Unknown/Other Function
Operating System: Win10
PHP Version: 7.4.15
Block user comment: N
Private report: N
New Comment:
yeah, well ArrayIterator([]) will create new array and then new object to basicly return nothing,
right? Ok the thing with those return statements inside generators is kind of confusing still to me.
However ok. It would be nice to have static/const object of empty iterator, just so you don't
have to create instance every time. But yeah, I will just make it in utilities class I guess.
Previous Comments:
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[2021-02-12 15:39:43] requinix@php.net
1. You can end a generator by return;ing.
2. An empty Generator from a function that doesn't even have code to yield anything
doesn't make sense. Just return an empty iterator, like ArrayIterator([]).
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[2021-02-12 08:43:35] petr dot vejchoda at seznam dot cz
Description:
------------
I was looking for a way to end a end a generator prematurely without necessity to make it to the end
of function/method. Also way of marking a function/method as an empty generator. And I found none.
If there is one, one can say I can't google properly, or one could also say it was not written
in the documentation.
Test script:
---------------
abstract class Base
{
__construct()
{
foreach($this->generator() as $key => $value)
{
$this->doSomething($key, $value);
}
}
protected abstract function generator(): traversable;
}
class Child extends Base
{
// empty generator??
protected function generator()
{
if (false)
{
yield null;
}
}
}
Expected result:
----------------
I would appreciate some language construct like yield break; that would end the generator
prematurely, or could be used to simplify empty generator syntax.
yield from new EmptyIterator(); is not really an option for me, sorry, thats just plain ugly.
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Edit this bug report at https://bugs.php.net/bug.php?id=80735&edit=1
Thread (5 messages)