Given a template T(uint N), int values for N are implicitly cast to uint where N is used within the template body. However, the instantiation of T!(n) precedes the coercion of n to uint such that the template instances T!(1) and T!(1u), and any types defined within them, are distinct. I believe this should not be the case.

Reproduced with DMD 1.046 under Linux and LDC r1522 under Solaris. Test case and compiler output below:
---
module Test;

struct Test(uint N)
{
  int x;

  Test!(N) f(Test!(N) rhs)
  {
    return Test!(N)(x+rhs.x);
  }
}

void main()
{
  Test!(1) x;
  x.f(x);
}
---
Test.d(16): Error: function Test.Test!(1).Test.f (Test!(1u)) does not match parameter types (Test!(1))
Test.d(16): Error: cannot implicitly convert expression (b) of type Test!(1) to Test!(1u)