> On Apr 14, 2016, at 10:50 PM, Chris Lattner via swift-evolution > <swift-evolution@swift.org> wrote: > > On Apr 14, 2016, at 10:40 PM, John McCall <rjmcc...@apple.com> wrote: >>>> To me, the unparenthesized style suggests that the input and output are >>>> peers, which feels more natural for the sort of value-to-value >>>> transform/predicate where this most commonly occurs. Parenthesizing the >>>> input feels fussier, which contributes to a sense that the argument is >>>> just one component to producing the result. >>>> The parentheses are grammatically unnecessary in most cases (by frequency >>>> of use in higher-use programming, not by feature count). >>> >>> I agree with your point that many simple higher order programming examples >>> (e.g. map, filter, etc) take a single argument. That said, I don’t agree >>> that this means that we should syntactically privilege this special case. >> >> "Special case" is a loaded phrase. Why is it a special case as a parameter >> if it isn't a special case as a result? > > Because, as I tried to explain in my original post, parameters *are* a > special case. The result type of a function is just a type. The parameter > list allows things that types do not: default arguments and variadics.
Parameters also support different API vs internal parameter labels as well. -Chris _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution