struct CantCopyThis; struct IWantToCopyThis { but_i_cant: CantCopyThis, } impl Copy for IWantToCopyThis {} //~^ ERROR the trait `Copy` cannot be implemented for this type enum CantCopyThisEither { A, B, } enum IWantToCopyThisToo { ButICant(CantCopyThisEither), } impl Copy for IWantToCopyThisToo {} //~^ ERROR the trait `Copy` cannot be implemented for this type fn main() {}