To help LDC/GDC

[deadalnix]

On Wednesday, 10 April 2013 at 18:33:26 UTC, Walter Bright wrote:
> On 4/9/2013 7:12 AM, Simen Kjærås wrote:
>> const is not sufficient, as someone else might have a mutable
>> reference. immutable is needed.
>
> const is sufficient for strongly pure, because another 
> reference is not available to the function body, and so the 
> function cannot mutate it.

No !

A delegate reached via parameters and called can mute them.

call with const parameter can be considered strongly pure if the 
argument is immutable (granted we fix delegate transitivity 
issues).