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Date: Sat, 16 May 2020 14:52:35 +0200
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To: PHP internals <internals@lists.php.net>
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Subject: Re: [PHP-DEV] [RFC] Guard statement
From: tovilo.ilija@gmail.com (Ilija Tovilo)

Hi Pavel

> https://wiki.php.net/rfc/guard_statement
> <https://wiki.php.net/rfc/unbundle_xmlprc>

First of all, thanks for your proposal!

I'm a bit skeptical. guard is mostly useful in Swift because it's a
strictly typed language.

let x = foo() // type Int?
if x == nil { return }
// x is still Int?

Guard is kind of an inverted if statement for them.

guard let x = foo() { return }
// x is Int

In PHP we don't have this problem as there are no (or few) compile
time type checks.

guard (null !== $x = foo()) { return; }
// No benefit over
if (null !== $x = foo()) { return; }

The only benefit is that the block is forced to be terminating but
that's not worth it IMO.

Ilija