Why a template with Nullable does not compile?

[Victor Porton via Digitalmars-d-learn]

Why does this not compile?

import std.typecons;
template FieldInfo(T, Nullable!T default_) {
}

/usr/lib/ldc/x86_64-linux-gnu/include/d/std/typecons.d(2570,17): 
Error: `alias T = T;` cannot alias itself, use a qualified name 
to create an overload set
/usr/lib/ldc/x86_64-linux-gnu/include/d/std/typecons.d(3291,17): 
Error: `alias T = T;` cannot alias itself, use a qualified name 
to create an overload set