Swift Unwrapped

Introduce User-defined "Dynamic Member Lookup" Types: First version: https://github.com/apple/swift-evolution/pull/768 Second version: https://github.com/apple/swift-evolution/pull/774 Implementations: First version: https://github.com/apple/swift/pull/13076 Second version: https://github.com/apple/swift/pull/13361 Related "dynamic callable" proposal (gist in progress): https://gist.github.com/lattner/a6257f425f55fe39fd6ac7a2354d693d Chris’s email to Swift Evolution: https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20171113/041463.html Leave a review on iTunes and join http://spectrum.chat/specfm/swift-unwrapped