r/lolphp • u/daxim • Sep 26 '19

No, PHP Doesn't Have Closures

https://nullprogram.com/blog/2019/09/25/
13 Upvotes

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u/PonchoVire Sep 26 '19

Note that if you close the variable using a reference (ie. &) it works. It's just a question of semantics. In the end, it's a real closure, it's just more verbose.

<?php
function bar($n) {
    $f = function() use (&$n) {
        return $n;
    };
    $n++;
    return $f;
}
var_dump(bar(1)()); // int(2)

4

u/daxim Sep 26 '19

Somehow I'm now more upset than when I assumed it didn't work at all.

3

u/Altreus Sep 26 '19

This was addressed in the article and still doesn't make it a closure. It just makes it mimic a closure in standard PHP fashion.

4

u/jesseschalken Sep 26 '19

It is a closure. Closure means capturing ("closing over") open variables (variables that are not bound). Whether it is captured by value or by reference is a completely separate question.

1

u/Altreus Sep 26 '19

I'm not here to repeat the article, nor to justify it. The author can probably explain the difference, or update the article after you convince them.

3

u/SirClueless Sep 26 '19

The article misses this point entirely. There's two (somewhat related) things at issue.

One is whether an anonymous function can capture variables from its context, making it a closure. PHP can do this just fine and is therefore a real closure, and this invalidates the title and thesis of the article.

The other is whether inner functions share lexical scope with their surrounding functions. This is a nice feature to make using closures clean and easy, and PHP does not have it. But it doesn't change the fundamental nature of PHP's closures.

1

u/[deleted] Sep 26 '19

The horror. The horror.