Andy Matuschak on Twitter: "@kongtomorrow @brentsimmons That requires making a 1-to-1 relationship between each `Smashable`-adopter and each `Value`-adopter" / Twitter

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Ken Ferry

@kongtomorrow

Jun 21, 2015

@brentsimmons

I think you're after "associated types". developer.apple.com/library/ios/do Gist: gist.github.com/kongtomorrow/7

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That requires making a 1-to-1 relationship between each `Smashable`-adopter and each `Value`-adopter

6:17 PM · Jun 21, 2015Twitter Web Client

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actually I realized that I'm not sure about intent. Updated gist. Seems like Smashable should extend value?

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Don’t see why Smashable and Value would be related in the type hierarchy.

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Which can make for better diags + perf, but not necessary: gist.github.com/andymatuschak/

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Does that permit Brent’s use case, where it accepts one Value but returns a different one?

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Right. Value can't be directly Equatable and used as a dynamic type currently.

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You could put an "isEqual(Value)" method on Value to model heterogeneous equality.

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