import std.traits;

struct Vector
{
	float x,y,z,w;
	immutable Vector one = Vector(1,1,1,1);
}

void func(int x = 10, ref const Vector v = Vector.one);

static if(is(typeof(func) PT == __parameters))
	pragma(msg, PT);


Output: (int x = 10, ref const(Vector) v = one)

Notice: 'one' has had the 'Vector.' removed from infront, it is no longer a valid identifier.
It'd be nice if that string would rather produce a fully justified name: (int x = 10, ref const(Vector) v = modulename.Vector.one)
This way it would remain a valid identifier, and usable in mixins.

Walter has some reservations about making this change, concerned it may be a breaking change.

I argue that the only reason anyone would want to use this string is for something like a mixin, and encouraging people to write a large system around this functionality to parse the string and put 'Vector.' back on is not something you want to stick with. (this is what I was tempted to do, but dismissed it on basis of insanity)