Hello Itai, Thanks for your response and its explanations!
Agreed that comprehension of multiple formats is important since there are a couple common ways of encoding JSON dates! Still, ISO 8601 appears pretty often (though I don’t have data on that, Stack Overflow says RFC 7493 I-JSON prefers ISO 8601; https://tools.ietf.org/html/rfc7493#section-4.3), and as other servers might make/handle a lot of JSON produced to/from the API, I think it would be disadvantageous to default to `deferredToDate` (if `deferredToDate` doesn't use the ISO 8601 format). As you mention, writers/readers have to agree on their format - my 2¢ is that ISO 8601 would be more common, and so a better default, than a Unix or reference date timestamp. Regards, Will Stanton -—Gracias for the prediction :-) > On Mar 15, 2017, at 9:53 PM, Itai Ferber <ifer...@apple.com> wrote: > > Hi Will, > > Thanks for your comments! > deferredToDate simply uses the default implementation that Date provides — > since it is not a primitive type like Int or String and conforms to Codable > itself, it will have an implementation of init(from:) and encode(to:). It > will have an implementation that makes sense for Date in general, but since a > big use-case for JSON lies in talking to external servers which you don't > control, allowing for custom date formatting is important. > > To that end, although ISO 8601 may make sense for some applications as the > default, it is less efficient to format, encode, decode, and parse than, say, > writing out a UNIX timestamp as a Double (or similar). Thus, the default is > to allow Date to pick a representation that best suits itself, and if you > need customization, you have the option to use it. > > Since Date makes a concrete decision about how to encode, both sides will > need to use deferredToDate for compatibility, in the same way that they would > have to agree about ISO 8601, or any of the other options. > > HTH! > > — Itai > > P.S. About Xcode autocompletion slowdown, I don't know to be honest, but I > can't imagine it would be significant. Only certain types have enc... or > dec... and even then, the list of methods isn't that long. _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution
