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Date: Mon, 23 Sep 2013 20:45:17 +0100
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Subject: Re: [PHP-DEV] Argument unpacking - Multiple unpacks and trailing
 arguments
From: ajf@ajf.me (Andrea Faulds)

On 23/09/2013 20:33, Nikita Popov wrote:

> The main open question (or at least the focus of the discussion) seems to
> be whether to allow multiple unpacks and trailing arguments.
>

I'm not sure I like the idea of multiple unpacks, were we to implement 
named parameters (if you did f(...(['a' => 2]), ...(['a' => 3])) you'd 
presumably have the $a argument overridden?), but I can't oppose it for 
linear arguments alone.

I'm not sure about trailing arguments either. I'm not sure if there's 
really a good use case for them.

I notice that we do not allow either in the variadics RFC, so I think it 
would make sense to be consistent with that. If someone really needs to 
do either of these, it would be a simple array_merge() away, and that 
might make the code clearer.

I also note that Python doesn't allow either of these. I can't find why 
exactly, but I would assume there were good reasons behind it.

So I think it would be best to allow neither of those, for the sake of 
consistency.

(OT: I've also just discovered that Python supports "a, b, *c = someseq" 
for multiple assignment, perhaps we could see "list($a, $b, ...$c) = 
$someseq" support?)

-- 
Andrea Faulds
http://ajf.me/