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Date: Tue, 19 Jan 2016 11:49:41 +0000
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Subject: Re: [PHP-DEV] [RFC] Allow specifying keys in list()
From: lester@lsces.co.uk (Lester Caine)

On 19/01/16 01:35, Andrea Faulds wrote:
>> $point = new Point(21, 42);
>> list('x' => $x, 'y' => $y) = $point;
> 
> You can't do `$x = $point['x'];`, so `list("x" => $x) = $point;` won't
> work either. If you want list() support, implement ArrayAccess.
> 
> We could potentially add some extension to list() for object
> destructing, but I'm not sure I'd be happy with that, as list() has
> thus far been an array-only thing. 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.

My real world example is from probably 15+ year old code which has to be
re-factored these days to actually work. It creates an 'object' or list
of objects as a multi level array to pass around and then uses extract()
to give a set of variables some of which may be arrays themselves ....
and some 'NULL' entries ... depending on just what the template is
building. The 'parsing' will select a function depending on the type of
a resulting element and perhaps pass on the extracted array if that is
what is provided.

I understand that modern practice is to actually define all the values
being used ( and type them ) but the flexibility that used to be
available seems to be lost by some of these new approaches when one now
expects an array of 'objects' rather than an array of 'elements' ? I
think that your 'destructuring' is the difference between my simply
using the array value and having to find the value of a private variable
in the object?

Since I am invariably working with associated arrays, 'list' is not
something in my toolkit, which is why using it will require rethinking,
but simply tidying 'extract' to create a matching set of variables
inside the object would make sense in my method of working. Every
persistent object comes into me as an associated array, so I'm trying to
see how this might improve my own code since the current practices are
no longer PC.

-- 
Lester Caine - G8HFL
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