Re: Does D support nested Templates aka Higher Kinded Polymorphism?

[sighoya via Digitalmars-d-learn]

On Tuesday, 3 October 2017 at 15:30:52 UTC, Daniel Kozak wrote:
writeln(bar!(Bar,Foo,int)(Bar!(Foo,int)()));
Dne 3. 10. 2017 3:55 odpoledne napsal uživatel "sighoya via 
Digitalmars-d-learn" <digitalmars-d-learn@puremagic.com>:

But when I write this to:

writeln(bar!(Bar,Foo,int)(Bar!(Foo,int)));

it complains by:

test.d(11): Error: template instance T!(S!int) does not match 
template
declaration Bar(R, S)
test.d(11): Error: template instance T!(S!int) does not match 
template
declaration Bar(R, S)
test.d(17): Error: template instance test.bar!(Bar, Foo, int) 
error
instantiating

I still get

test.d(11): Error: template instance T!(S!int) does not match 
template declaration Bar(R, S)
test.d(11): Error: template instance T!(S!int) does not match 
template declaration Bar(R, S)
test.d(18): Error: template instance test.bar!(Bar, Foo, int) 
error instantiating


by

struct Foo(T) {
        T value;        
}

struct Bar (R,S) {
        R!S fooint;
}


//T!S foo(S, alias T)(T!S v) { return v; }
T!(S!R) bar(alias T,alias S,R)(T!(S!R) v) {return v;}


void main() {
        import std.stdio;       
        //writeln(foo!(int, Foo)(Foo!int(1)));
        //writeln(bar!(Bar,Foo,int)(Bar!(Foo,int)));
        writeln(bar!(Bar,Foo,int)(Bar!(Foo,int)()));
}