> On Apr 26, 2016, at 11:42 AM, Chris Lattner via swift-evolution > <[email protected]> wrote: > > On Apr 26, 2016, at 8:47 AM, Tony Allevato via swift-evolution > <[email protected]> wrote: >> That seems like a purely syntactic concern that could potentially be >> addressed in other ways, though. I'm not sure the choice of "duplicate all >> operators using verbosely-named methods" is the best one for the reasons I >> mentioned above, and the question of "how do we cleanly unify operators with >> other protocol requirements?" seems out-of-scope and orthogonal to this >> proposal. > > There is a strong motivation for this approach though: we want the type > checker to be scalable. John recently wrote an epic piece about why having > tons of overloads is a really bad idea: > https://lists.swift.org/pipermail/swift-dev/Week-of-Mon-20160404/001650.html > > It is *much* better for type checker performance to have (e.g.): > > func +<T : FloatingPoint>(lhs : T, rhs : T) -> T { return lhs.add(rhs) } > func +<T : Integer>(lhs : T, rhs : T) -> T { return lhs.add(rhs) } > > Rather than overloads for 4 floating point types, and 8+ integer types. We > really need to eliminate all the “expression too complex” classes of issues, > and this is an important cause of them.
Also, sorry for not being explicit about this. I’m not a type checker expert, but I believe that using operator requirements imposes the same load on the type checker as having large overload sets. -Chris _______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
