https://issues.dlang.org/show_bug.cgi?id=15550
--- Comment #1 from Martin Nowak <c...@dawg.eu> --- The bug boils down to this behavior change. cat > bug.d << CODE struct Vector(T, int N) { void opDispatch(string, U)(U) { } } static assert(!is(typeof(Vector!(int, 2)._isMatrix))); CODE dmd -c -o- bug ---- bug.d(9): Error: static assert (!true) is false ---- It works w/ 2.069.2. --