We need better documentation for functions with ranges and templates

[Meta via Digitalmars-d]

On Monday, 14 December 2015 at 20:53:53 UTC, Andrei Alexandrescu 
wrote:
> One thing we definitely need to do is make the template 
> constraints rendered better in documentation, and also allow 
> user content in them. We've discussed this several times but no 
> clear path emerged so far. Maybe a strong champion would come 
> forward?
>
> I'm thinking along the lines of:
>
> * Change ddoc to output the constraint separately under a 
> DDOC_CONSTRAINT macro.
>
> * Allow ddoc comments inside macros:
>
> bool isSameLength(Range1, Range2)(Range1 r1, Range2 r2)
> if (isInputRange!Range1 && isInputRange!Range2 && 
> !isInfinite!Range1 && !isInfinite!Range2
> /**
> `Range1` and `Range2` must be both non-infinite input ranges.
> */
> );
>
> then format that comment as a DDOC_CONSTRAINT_USERTEXT or 
> something.
>
> These would be good steps to take.
>
>
> Andrei

I'm not particularly familiar with DDOC. Is there some 
documentation on creating new macros?