On 03/10/2017 1:05 PM, sighoya wrote: > Especially, I mean something like > > T<S> foo(S,T)(T<S> i) > { > ... > } struct Foo(T) { T value; } T!S foo(S, alias T)(T!S v) { return v; } void main() { import std.stdio; writeln(foo!(int, Foo)(Foo!int(1))); }