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To: Stanislav Malyshev <smalyshev@gmail.com>,Nikita Popov <nikita.ppv@gmail.com>,PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Explicit call-site send-by-ref syntax
From: johannes@schlueters.de (=?ISO-8859-1?Q?Johannes_Schl=FCter?=)



On December 12, 2017 7:38:54 AM GMT+01:00, Stanislav Malyshev <smalyshev@g=
mail=2Ecom> wrote:
>Hi!
>
>> I would rather discourage usage of references=2E Since PHP 7 the cost
>of
>> breaking cow isn't as expensive anymore, but receiving values by
>value
>> and returning by value is more idiomatic imo=2E Using objects can be
>more
>> efficient=2E
>
>Objects are kind of overkill when you just need a modifyable array=2E And
>copying an array when you just need to add one value to a K-size array
>is still not a good idea for many apps=2E O(n) vs O(n^2) still matters=2E
>One should definitely be careful not to overuse refs, but there are
>still valid cases for using them=2E

The issue, as you well know, is that references disable copy-on-write=2E T=
hus assume you have code like this:

function with_ref(&$a) {
   count ($a);
}

function no_ref($a) {
  count($a);
}

The count in with_ref() will copy the array, while no_ref() can use copy o=
n write and won't actually copy=2E

johannes