Function template argument deduction

[Paul Backus]

On Saturday, 7 April 2018 at 06:26:24 UTC, Uknown wrote:
> What I did notice though is that when
> `string list2string(T)(List!T list)` was changed to
> `string list2string(T)(VariantN!(16LU, Nil, Tuple!(T, "head", 
> This*, "tail")) list)`
> The compiler correctly deduce `T` to be `int`

Interesting. Looks like this is an issue with aliases, because I 
get the error with this code too:

--- test.d
import std.typecons: Tuple, tuple;

alias Pair(T) = Tuple!(T, T);

void foo(T)(Pair!T p)
{
     return;
}

unittest {
     Pair!int x = tuple(1, 2);
     foo(x);
}
---