To help LDC/GDC

[Dicebot]

On Tuesday, 9 April 2013 at 14:50:58 UTC, Simen Kjærås wrote:
> On Tue, 09 Apr 2013 16:15:40 +0200, Dicebot 
> <m.strashun at gmail.com> wrote:
>
>> On Tuesday, 9 April 2013 at 14:06:31 UTC, Pelle Månsson wrote:
>>> shouldn't be strongly pure (as it can access mutable non 
>>> local state).
>>
>> I was under impression that pure is about verifying what 
>> function actually does, not what it probably can.
>
> It's based purely on function signature, so we're dealing with 
> possibles
> in many cases.

You got me lost here again. Definition of pure in dlang.org says: 
"To that end, a pure function:

* does not read or write any global or static mutable state
* cannot call functions that are not pure
* can override an impure function, but an impure function cannot 
override a pure one
* is covariant with an impure function
* cannot perform I/O"

It is all about behavior, not function signature. And function 
that takes ref parameter and does not read/write it is pure by 
this list.