Bug 17872 – 'lazy' on variadic template parameters is ignored

This assert fails: void foo(T...)(lazy T args) {} unittest { int n = 3; foo(n++); assert(n == 3); // Fails, n == 4. } This means there is no way to mark an arbitrary number of arguments of unknown types as lazy. A workaround exists for limited numbers, where (T1, T2, T3) is used in place of T..., but this solution does not scale.

Doesn't fail for me with dmd v2.076 on MacOS

You're right, I've misidentified the problem. This fails: void foo(T...)(lazy T args) { foreach (e; args) {} } unittest { int n = 3; foo(n++); assert(n == 3); } Which means the problem is not in the location I thought.