Oh man wouldn't it be cool if we could use this syntax like this:
void test(R1:isInputRange, R2:isForwardRange)(R1 r1, R2 r2) {}
I'm not sure how that would work with multiple constraints or
constraints that need comparisons, e.g. ElementType:
void test(R1:isInputRange && ElementType == int, R2:isForwardRange)() {}
Just throwing ideas for D5 there.. lol.
