inout delegate

[Manu via Digitalmars-d]

On 7 October 2016 at 05:58, Jinx via Digitalmars-d
<digitalmars-d at puremagic.com> wrote:
> On Thursday, 6 October 2016 at 15:00:56 UTC, Manu wrote:
>>
>> On 6 October 2016 at 00:29, Manu <turkeyman at gmail.com> wrote:
>>>
>>> On 4 October 2016 at 11:15, Manu <turkeyman at gmail.com> wrote:
>>>>
>>>> [...]
>>>
>>>
>>> I'm really struggling with this issue.. multiple times a day.
>>> I can't find a reasonable workaround. casting, or trying to re-synth
>>> the delegate type from the function signature doesn't seem to be
>>> reasonable. I lose all the attributes, and storage class on parameters
>>> are an endless nuisance that should never have existed. Cloning the
>>> function signature verbatim, but with inout resolved seems to be
>>> really hard and probably buggy.
>>> I really just need this bug fixed... is it a particularly tricky fix?
>>
>>
>> Goodnight. I'm really hoping I wake up tomorrow and someone has some
>> comment on this issue...
>> I'm a post about it every day. I'm completely blocked while this
>> regression stands ;)
>
>
> Why not make a template function that does the necessary conversion? Going
> from the delegate to a void* then back again with the appropriate attributes
> applied by a cast?

storage class and attributes are so hard to work with. It's a serious
pain to do what you suggest.
Since this is a bug (and a very recent regression no less), I just
want it fixed so I can get on with it. Writing massively complex
workarounds for it is just not worth the energy. Seriously, I'm sure I
could spend a whole day on it trying to cover all cases!

Perhaps you'd like to give it a go ;)

Something like:

template delegateTypeForInoutMethod(T, string method)
{
  alias delegateTypeForInoutMethod = [write lots of stuff here];
}

struct S
{
  inout(int)[] f(ref const(int) arg) inout pure nothrow { return [ arg ]; }
}

static assert(delegateTypeForInoutMethod!(const(S), "f") ==
const(int)[] delegate(ref const(int)) pure nothrow, "You failed!");