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Date: Sat, 26 Sep 2015 20:05:55 +0100
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Subject: Re: [PHP-DEV] Arrow function expressions in PHP
From: rowan.collins@gmail.com (Rowan Collins)

On 26/09/2015 19:37, Levi Morrison wrote:
>> Thank you for the feedback. I feel like the rest of what you proposed
>> was a bit too far outside of the box. For what it is worth no token
>> after the paren is necessary – you could do `fn($x) $x * 2` (or
>> `function($x) $x * 2`). I think this is a case where more syntax
>> helps.
> Here they are on separate lines so you can see things more clearly:
>
>      $output = array_map(function($x) $x * 2, $input);
>
>      $output = array_map(function($x) => $x * 2, $input);
>
> I think the arrow helps.

I meant more that the lack of parens around the whole expression looks 
odd - the => is no longer just an operator linking two expressions, it's 
an arbitrary piece of syntax inserted just because it feels like 
something should go there (and I agree it does look more readable than 
nothing at all).

How about a variant on existing curly braces:

fn($x) { $x * 2 }
lambda($x) { $x * 2 }

Or the arrow inside the parens:

fn($x => $x * 2)
function($x => $x * 2)

My point is that there are plenty of other variants, if we're no longer 
mimicking the "(params) => expression" syntax of other languages.

Regards,

-- 
Rowan Collins
[IMSoP]