It would be consistent to move is_tuple_like<> to fmt namespace too.

@Remotion what about is_like_std_string, should I move that to fmt as well?

Moved is_tuple_like as well.

Then may be it was not great idea to do this in this PR as well ?
#763

what about is_like_std_string, should I move that to fmt as well?

I think yes.

I think yes.

Actually looking at it again it looks to only be used in is_range so I don't see much value in moving is_like_std_string as well.

Merged, thanks!