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Date: Mon, 23 Feb 2015 22:36:08 +0100
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Subject: Mark some functions with PREFER_REF
From: nikita.ppv@gmail.com (Nikita Popov)

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Hi internals!

With regard to my E_STRICT RFC [1] Yasuo and another off-the-record mail
expressed a concern about the "Only variables should be passed by
reference" strict standards warning.

This notices makes sense in a lot of places, e.g.

    array_push(getArray(), 1, 2, 3);

is totally pointless code if getArray() doesn't return a reference.
array_push will just modify a temporary array in this case.

However other usages like

    $top = array_pop(getArray());

are less clear: array_pop() both has a side-effect (removing the top
element of an array) and a meaningful return value (the top element of the
array). As PHP does not have a dedicated function for getting the
first/last element of an array, many people use code like this (which
currently throws E_STRICT) instead.

I'd like to mark a few such functions with PREFER_REF (i.e. allow passing
both references and values). In particular array_pop() and array_shift().

Does anybody have a problem with us doing this? Are there other functions
which should use PREFER_REF?

The motivation behind this is to make sure we only throw this notice in
cases where the code is actually buggy/nonsensical instead of just making
people ignore it altogether.

Thanks,
Nikita

  [1]: https://wiki.php.net/rfc/reclassify_e_strict

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