Is this something that should work (i.e., is it a bug)? abstract AbstractX{N}
type A{T} end type B{T, N, X <: AbstractX{N}} x::X t::NTuple{N, A{T}} end I get the error message *ERROR: N not defined* The line in question is the type declaration for B. I certainly get that this could be outlawed … but it seems that *similar* declarations are OK. And if I comment out *either* of the two fields of B, it works just fine. (Commenting out other parts of the example quickly leads to something that works, too, though I'm not seeing the logic in it at the moment.)