Why D is annoying =P

[Mehrdad]

Is there any reason why we don't have something like this in 
Phobos?



hash_t toHash(T)(in T t) if (isIntegral!(T) || isSomeChar!(T))
{
	return t;
}

hash_t toHash(T)(in T[] t)
{
	typeof(return) h = 0;
	foreach (item; t)
	{ h = h * 37 + item.toHash(); }
	return h;
}

hash_t toHash(T)(in T t) if (!isIntegral!(T) && !isSomeChar!(T) 
&& !isArray!(T))
{
	typeof(return) h = 0;
	foreach (ref a; t.tupleof)
	{ h = h * 37 + a.toHash(); }
	return h;
}

hash_t toHash(T...)(in Tuple!(T) t)
{
	typeof(return) h = 0;
	foreach (item; t)
	{ h = h * 37 + item.toHash(); }
	return h;
}