Pop quiz, what does this do?

[Simen Kjærås]

On Wednesday, 3 March 2021 at 16:33:35 UTC, Stefan Koch wrote:
> On Wednesday, 3 March 2021 at 16:31:53 UTC, Stefan Koch wrote:
>> On Wednesday, 3 March 2021 at 16:06:48 UTC, Steven 
>> Schveighoffer wrote:
>>> The FieldNameTuple from std.traits returns a tuple of names 
>>> of all the fields that are present on a type instance.
>>>
>>> What about the result on things that can't have fields?
>>>
>>> import std.traits;
>>>
>>> interface I
>>> {
>>>    int foo();
>>> }
>>>
>>> pragma(msg, FieldNameTuple!I);
>>>
>>> Without looking up the docs, or trying it, what do you think 
>>> it does?
>>>
>>> -Steve
>>
>> My feeling is that it returns tuple("foo").
>> But based on the name that probably shouldn't happen.
>
> Huh ... it works as it should in this case.
> Pleasant surprise :)

No it doesn't. Look again.

--
   Simen