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Date: Thu, 16 Jan 2014 20:20:35 +0000
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Subject: Re: [PHP-DEV] Introducing "Array Of" RFC
From: ajf@ajf.me (Andrea Faulds)



On 16/01/14 20:14, Andrey Andreev wrote:
> Am I the only one who finds both proposed syntaxes somewhat confusing?
>
> The originally proposed 'Bar[]' simply looks strange.

It is, however, familiar to C, C++, C# and Java users.

> So, how about this:
>
>    Array[Bar] $a - $a is array containing only instances of Bar
>    Array[Bar|null] $a - $a is array containing Bar instances or nulls
>    Array[Bar] $a = null - $a is either null or array containing only
> instances of Bar
>    Array[Bar|null] $a = null - above, but the array can contain nulls

That doesn't make much sense as a syntax, IMO. It looks like "Bar" is 
the index of the Array here. Surely it could use angle brackets, which 
would be familiar to people who've dealt with generics (C++, C#, Java 
users):

      Array<Bar> $a

> It's easily readable and everybody should be able to recognize what this
> thing does even without prior knowledge.

It's not clear to me at all at first glance. Is that a Bar-indexed array?

> Or even (at a later stage):
>
>    Array[]["key1", "key2"]
>
> ... which would hint for a numeric index array containing associative
> arrays that in turn must have the defined keys. This is indeed a bit crazy,
> but possible to add in the future without BC breaks. You could even shove
> scalar typehints in there as soon as they are implemented.

...that's even less intuitive to me.
-- 
Andrea Faulds
http://ajf.me/