Trying to use a template class with ranges

[mark]

On Thursday, 6 February 2020 at 16:29:57 UTC, Steven 
Schveighoffer wrote:
> On 2/6/20 11:05 AM, mark wrote:
>> src/package.d(50,35): Error: no property opCall for type 
>> diffrange.Diff!(dchar[]), did you mean new Diff!(dchar[])?
>
> Hah, forgot that it's a class. Yes, I DID mean new Diff ;)
>
> -Steve

Wow, that's all it needed to compile!

And I've added the extra check you suggested:

auto differ(T)(T a, T b) if (
         isForwardRange!T && // T is a range
         is(typeof(T.init.front == T.init.front)) // Elements 
support ==
         ) {
     return new Diff!T(a, b);
}

Thanks!