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Date: Fri, 22 Apr 2016 15:55:15 +0100
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Subject: Re: [PHP-DEV][RFC] Callable Types
From: rowan.collins@gmail.com (Rowan Collins)

Levi Morrison wrote on 22/04/2016 15:39:
> It would also allow for a general type-aliasing mechanism for single
> names. This feature has been asked for in the past but I can't
> remember the use-cases so this example is not very good:

One use I've seen is for making the "semantic type" of a scalar more 
obvious. I'd quite like to be able to do this:

type timestamp = int;
function format_date(timestamp $foo) { ... }

Any integer is a valid Unix timestamp, so you don't even need domain 
types in this case, although those would be even better:

type age = int { min: 0 };
type day_of_month = int { min: 1; max: 31 };

Regards,
-- 
Rowan Collins
[IMSoP]