>       • What is your evaluation of the proposal?

Very large +1 in general.  I really wanted to see this happen in Swift 4.  I’m 
very happy that it’s up for review right at the beginning of the Swift 5 

That said, I do think the concern others have voiced regarding implicit 
synthesis has some merit.  Most languages I am familiar with that synthesize 
memberwise implementations do so using an explicit request (`deriving` or 
similar).  It adds a small amount of boilerplate in exchange for precise 
control.  It seems to me that this tradeoff is in line with Swift’s motto of 
clarity over concision.  If we do make a change to this proposal we should also 
make the same change for basic enums as well as Codable for the sake of 

>       • Is the problem being addressed significant enough to warrant a change 
> to Swift?

Yes.  Manually writing memberwise implementations is a big enough annoyance 
that it can influence designs.  For example, a library author may be more 
likely to try and avoid requiring user types to conform when users are required 
to write those conformances manually. 

>       • Does this proposal fit well with the feel and direction of Swift?

Very much so.

>       • If you have used other languages or libraries with a similar feature, 
> how do you feel that this proposal compares to those?

It is very similar, although as mentioned, it might make sense to require 
explicit opt-in to memberwise synthesis.

>       • How much effort did you put into your review? A glance, a quick 
> reading, or an in-depth study?

Quick glance this time around, but I have participated heavily in the previous 

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