https://issues.dlang.org/show_bug.cgi?id=16957
--- Comment #2 from John Colvin <john.loughran.col...@gmail.com> --- template a(alias b) { alias T = typeof(b); auto a(T ret) { return ret; } } auto a(T, size_t N)(T[N] a) {} // breaks // auto a(T)(T[] a) {} // OK void main() { int x; auto b = a!(x); } test.d(5): Error: undefined identifier 'T' test.d(16): Error: cannot infer type from template instance a!(x) --