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Subject: Re: [PHP-DEV] Little switch improvement: get the used variable
From: rowan.collins@gmail.com (Rowan Collins)

Rowan Collins wrote (on 24/09/2014):
> On 24/09/2014 22:33, Andrea Faulds wrote:
>> On 24 Sep 2014, at 22:17, Rowan Collins <rowan.collins@gmail.com> wrote:
>>
>>> Perhaps rather than a magic function or constant, though, the switch 
>>> statement could be extended with an "as" argument, which would store 
>>> the evaluated expression into a normal variable, allowing nesting, 
>>> and easier optimisation of the engine where the feature isn't used. 
>>> Thus you could write this:
>>>
>>> switch( some_expression() as $switch_value ){
>>>   case 1:
>>>     do_something();
>>>   break;
>>>   //...
>>>   default:
>>>     throw new Exception('Undefined input: ' . $switch_value);
>>>     break;
>>> }
>> Incredibly, some brave soul has gone back in time and already 
>> implemented this, when none of us was looking!
>>
>>      switch($switch_value = some_expression()) {
>>          ...
>>      }
>>
>
> Heh, now I feel like a fool for not thinking of that.
>
> Treating assigments as expressions just isn't something that jumps to 
> mind, I guess!
>

Anyone have any thoughts on the use(operator) part, though?

Am I missing something equally obvious there? Or just, it doesn't 
interest people much as an idea?

-- 
Rowan Collins
[IMSoP]