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Date: Wed, 20 Mar 2019 00:28:31 +0000
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To: Larry Garfield <larry@garfieldtech.com>
Cc: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] RFC Draft: Comprehensions
From: robehickman@gmail.com (Robert Hickman)

> > In python comprehensions on [] makes a list and comprehensions in {}
> > make a dictionary (list and dict comprehensions). As PHP only has one
> > 'array' type using [] makes sense. Along that train of thought, should
> > comprehensions also be possible in the old array() syntax?
>
> Honestly, I cannot think of any case where I'd use a comprehension where =
I would definitely want an array and not a generator.  In the majority case=
 both work equally well, cool, but I don't know when I would even use an ar=
ray-dependent version.  And converting from a generator to an array is triv=
ial; the other way, very not so much.
>

Would there be any notable performance difference? I'd expect the case
where one actually wanted the whole array to be slower if it was going
through a generator, vs a tight loop, due to the additional level of
indirection.