I have a type
typealias TColor RGBA{UfixedBase{Uint8,8}} typealias TImage Image{TColor, 2, Array{TColor, 2}} How do I know if it's a concrete type or not? Is there an isconcrete function somewhere? Incidentally, I'm asking this because I just updated my packages and had to adjust to the recent Colors changes. My former definition of TColor was: typealias TColor AlphaColorValue{RGB{UfixedBase{Uint8,8}},UfixedBase{Uint8,8 }} and now for whatever reason concatenating images together is ~10X slower. Since those are just arrays, I assume it's a type problem. Those are more frustrating and frequent than I expected, I must be doing something wrong... Cédric