__traits for checking if a type is dynamic array (slice)

[Eduard Staniloiu]

On Monday, 26 November 2018 at 09:28:37 UTC, Basile B. wrote:
> On Monday, 26 November 2018 at 09:04:25 UTC, Per Nordlöw wrote:
>> Why is there no
>>
>> - __traits(isArray, T)
>>
>> alongside
>>
>> - __traits(isStaticArray, T) and
>> - __traits(isAssociativeArray, T)
>>
>> when dmd already has `ENUMTY.Tarray` alongside
>>
>> - ENUMTY.Tsarray and
>> - ENUMTY.Taarray
>>
>> and std.traits already has a wrapper for this at
>>
>> https://dlang.org/phobos/std_traits.html#isDynamicArray
>>
>> ?
>>
>> Should we add this new builtin trait and use it in 
>> std.traits.isDynamicArray?
>>
>> If so, should we call it
>>
>> - __traits(isDynamicArray) or
>> - __traits(isArray) or
>> - __traits(isArraySlice) or
>> - __traits(isSlice) or
>>
>> something else?
>
> Yeah maybe just try, although i see some alias this implication 
> in the current std.traits implementation. Adding a new trait is 
> rarely a big deal as far as i could see in the past (i.e no big 
> never endings discussions).

This would be a nice addition, imho.

As Basile B is saying, there is quite a bit of work done for the 
`isDynamicArray` implementation. If you have the time to drill 
down from 
https://github.com/dlang/phobos/blob/master/std/traits.d#L6618

I was expecting the `isArray` check to be something like `enum 
isArray(T) = is(T == U[], U)`

I would like to see this in the compiler traits :D