Sent from my iPhone
> On Dec 5, 2017, at 12:19 AM, Cao, Jiannan via swift-dev <swift-dev@swift.org> > wrote: > > > But, I mean, what subscript (restrict to the length) could do is subset of p > replaceSubrange could do, right? True but that would imply the opposite of the refinement relationship you’re suggesting. A derived protocol has to have a subset of the behavior of the protocol it refines. _______________________________________________ swift-dev mailing list swift-dev@swift.org https://lists.swift.org/mailman/listinfo/swift-dev