• Per =?UTF-8?B?Tm9yZGzDtnc=?= (19/19) Nov 26 2018 Why is there no
• Basile B. (5/24) Nov 26 2018 Yeah maybe just try, although i see some alias this implication
• Eduard Staniloiu (9/45) Nov 26 2018 This would be a nice addition, imho.
• Per =?UTF-8?B?Tm9yZGzDtnc=?= (3/4) Nov 26 2018 https://github.com/dlang/dmd/pull/9014
• Andrei Alexandrescu (11/28) Nov 26 2018 Thanks for bringing this to my attention, Per.

Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

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?

Basile B. <b2.temp gmx.com> writes:

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).

Eduard Staniloiu <edi33416 gmail.com> writes:

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

Per =?UTF-8?B?Tm9yZGzDtnc=?= <per.nordlow gmail.com> writes:

On Monday, 26 November 2018 at 10:53:25 UTC, Eduard Staniloiu 
wrote:
 I would like to see this in the compiler traits :D

https://github.com/dlang/dmd/pull/9014

Andrei Alexandrescu <SeeWebsiteForEmail erdani.com> writes:

On 11/26/18 4:04 AM, Per Nordlöw wrote:
 Why is there no
 
 - __traits(isArray, T)
 
 alongside
 
 - __traits(isStaticArray, T) and
 - __traits(isAssociativeArray, T)


Thanks for bringing this to my attention, Per.

The core idea is to have __traits "primitive and ugly" and std.traits 
"convenient and nice". From that viewpoint, if isArray can be 
implemented as a library feature using primitives provided by traits, 
there is no need for making it.

 when dmd already has `ENUMTY.Tarray` alongside
 
 - ENUMTY.Tsarray and
 - ENUMTY.Taarray

Justifying the feature by means of a detail in the compiler 
implementation is definitely undesirable.

 and std.traits already has a wrapper for this at
 
 https://dlang.org/phobos/std_traits.html#isDynamicArray
 
 ?

If the wrapper works well, use it and move on.


Thanks,

Andrei