Force specialization on arguments in core wrapper

[KristofferC]

Sometimes defining a function as f(a, b, c) = g(a,b,c) might mean that the specialization heuristic kicks in when the type of an argument is a Function or Type. This leads to issues like JuliaLang/julia#28087 and #71.

One possible way around this is to force specialization using where (with an implementation in JuliaLang/julia#28087 (comment)). This might make sense since presumably, we want this core wrapper to be "as invisible as possible".

[KristofferC]

Closing in favor of #124.