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Date: Tue, 19 Jan 2016 16:18:52 +0000
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Subject: Re: [PHP-DEV] [RFC] Allow specifying keys in list()
From: rowan.collins@gmail.com (Rowan Collins)

Lester Caine wrote on 19/01/2016 11:49:
>> If we ever add object literals, then
>> >we could do object destructuring with a symmetrical syntax.
> Andrea, please bare with me as I'm trying to work out just what some of
> those long words actually mean.

I think what Andrea's getting at is being able to do something similar 
to what you can do in JS:

// Object literal: create an object with all its values
var foo = { a: 1, b: 2, c: 3 };
// Destructure an object into variables: take bits of an object that 
you're interested in all in one go
// equivalent to bob = foo.a; jane = foo.c;
var {a: bob, c: jane} = foo;

In PHP, we don't have either of these on objects - you can only create 
an object using a constructor function - but the proposal is basically 
the same thing for associative arrays (which are in some ways similar to 
JS objects anyway):
// Array literal
$foo = ['a' =>  1, 'b' => 2, 'c' => 3];
// Destructuring with list()
list('a' => $bob, 'c' => $jane);

So it's like extract(), but both more powerful and less dangerous - you 
don't get an unexpected variable $b when someone adds a key to the 
array, and you have the ability to rename $a and $c while you're 
extracting them.

It may or may not work for your use case, but it doesn't really have 
anything to do with objects either way.

Regards,
-- 
Rowan Collins
[IMSoP]