on Tue Nov 01 2016, Jens Alfke <swift-users-AT-swift.org> wrote: >> On Nov 1, 2016, at 10:40 PM, Zhao Xin <owe...@gmail.com> wrote: >> >> For example, if I want show the user that I have to ask him to give me >> permission of a folder, the > `url.path` has no need to translate. > > We’re getting off-topic, but paths do need to be translated, at least > on Mac systems. The names of many standard folders like “Applications” > and “Documents” are hardwired to English in the filesystem but are > localized in the UI. Some application names get localized too (there’s > a table in the app’s Info.plist that can substitute localized names.) > > Anyway, string interpolation is convenient, but I wouldn’t say it > should be the only way to format strings in Swift; it’s a lot less > flexible than the C-style “%” substitutions. For comparison, even > though C++’s iostreams use “<<“ to format strings by concatenation, I > still end up using “%” based formatting a lot, depending on the use > case.
I'm actually working on design in this area right now. %-style formatting has the following drawbacks - for anyone who doesn't use them regularly they are cryptic and complex, as the printf (3) man page attests. - the spelling of these placeholders must match up to the types of the arguments, in the right order, or the behavior is undefined. Some limited support for compile-time checking of this correspondence could be implemented, but only for the cases where the format string is a literal. - there's no reasonable way to extend the formatting vocabulary to cover the needs of new types: you are stuck with what's in the box. In my opinion, we can and must do much better for Swift. If there's something about “%” formatting that you particularly value, I'd like to know about it, so I can make sure it's accomodated. Thanks, -- -Dave _______________________________________________ swift-users mailing list swift-users@swift.org https://lists.swift.org/mailman/listinfo/swift-users
