Some generics type inference questions

[hooman (Hooman Mehr)]

It is a limitation for performance reasons. It can get really complicated and slow down compilation if it goes up multiple levels. See this thread:

[Pitch] Remove type inference for associated types

Hello all, Per Chris Lattner's list of open Swift 3 design topics (http://article.gmane.org/gmane.comp.lang.swift.evolution/21369\), I've put together a proposal for removing type inference for associated types. It can be found here: https://github.com/austinzheng/swift-evolution/blob/az-assoctypeinf/proposals/XXXX-remove-assoctype-inference.md Thoughts, criticism, and feedback welcome. There are at least two slightly different designs in the proposal, and I'm sure people will have ideas for …