I'll stick with Gwynne here. Each language has its syntax for interpolating string and as such I don't see a reason to change this. As for formatting, I agree it is an issue but we have to remember that inside \() we have code that can do pretty much everything one may need. You may even add a formatting function to String or Int in order to produce the result you need (even simplifying the calls to NumberFormatter - I myself have a whole library of "shortcuts" I add to every project).
L On 21 June 2016 at 18:49, Gwynne Raskind via swift-evolution <swift-evolution@swift.org> wrote: > On Jun 21, 2016, at 15:48, Jonathan Cotton via swift-evolution > <swift-evolution@swift.org> wrote: > > I'd support $() as is in use by other languages, including Kotlin, as > mentioned it seems less disruptive and more inline with the tokenised > parameters that are already supported in closures. > > On 21 Jun 2016, at 21:43, Kenny Wyland via swift-evolution > <swift-evolution@swift.org> wrote: > > Hi all, > > I'm new to the list and I just searched through the archives as best I could > to see if someone else had already brought this up, but I didn't find > anything. Forgive me if this horse has been beaten. > > I find that typing \(var) is very disruptive to my typing flow. The more I > code in Swift, the more I like it, but every time I'm coding and then have > to hiccup while typing \ then ( causes me to be annoyed. I know, it's minor, > but it isn't a key combination that flows quickly. > > I would much rather have $() or perhaps ${} (like Groovy lang) or perhaps > @() to go along with other uses of @ throughout the language. > > A shifted key, like $ or @, followed by another shifted key like (, allows > for a much faster flow and they are much closer to the home keys than \ > which is nearly as far from home keys as possible (and awkward). > > Thoughts? > > Kenny Wyland > InADayDevelopment.com > > > I have to disagree - The \ syntax is consistent with other string escape > sequences (\n etc.) and reads naturally to me in that regard. Additionally, > the \ is very visually distinctive in a string, much moreso than the > "traditional" $ variable marker. Almost every language I’ve seen using $ for > interpolation in strings is doing so because it also uses it as a variable > prefix in non-string contexts. To top it off, using $ instead would, for me, > just add yet another language for which I have to remember "does the $ go > inside or outside the name delimiter braces/brackets/whatever?", "is it > parenthesis, braces, brackets, or some other delimiter for variable names?", > "what kind of expressions can I use in this context?", "can I use > interpolation without any delimiters for simple cases?", etc. See also PHP, > Perl, ten flavors of shell scripts, JavaScript, JSP/ASP, XPath, and so > forth. The \() syntax is unique to Swift and therefore very easy to > remember. > > I also don’t see that Swift carries an expectation of being able to use a > syntax which is traditionally confined to interpreted/scripting languages, > and even there $ is by no means ubiquitous. Here are just a few > counterexamples among various languages: > > - C (printf formats) > - C++ (stream modifiers) > - Objective-C (NSString formats) > - C# ($, but with the unusual syntax $"blah {foo} blah") > - Lua (printf formats and language hacks) > - Python (printf formats with trailing "% (tuple)" syntax) > - Ruby ("#{}") > - Java (printf formats) > > There’s an obvious pattern in these example, which brings to something I > _would_ like to see for string interpolation in Swift: Better control over > the precise representation of the data. I’m sure the topic has been done to > death many times before, but I haven’t found any solid information at a > quick search, so I apologize if this is all old hat. > > Anyway - Creating, configuring, and invoking various Formatter types in > order to present data in the proper fashion is an option, and a preferable > one when the data is intended for user consumption (especially to get the > maximum support from localization). But for logging, debugging, parsing of > textual formats, writing textual formats, etc., I almost always want a > traditional C/POSIX/ISO representation as easily provided by printf()-style > specifiers. 99% of the time when I want to do an number-to-string (integer > or otherwise) conversion especially, I’m being specific about the appearance > of the number. > > For example, for a hex representation of sockaddr_in.sin_addr.s_addr, I > would in other languages write "printf("0x%08x", address.sin_addr.s_addr);", > or "%02hhu" times four to get dotted-decimal notation. (Ignoring for the > moment the existence of inet_ntop() for the sake of the example :). In > Swift, I currently have to make a call to printf(), fprintf(), dprintf(), > NSString(format:), asprintf() (with a wrapper to deal with getting a > Swift.String from allocated memory), etc. A configured NumberFormatter > instance is a great deal more code - even > NumberFormatter.localizedString(from: foo, number: .decimal) is very > verbose, and that *still* doesn’t yield the same level of format control!). > > And to top it off, these still carry the traditional problem of printf() > formats - separation between the format specifier and the data that format > applies to. I’m sure most of us have at one time or another written a > printf() with enough arguments that it was easy to lose track of them and > end up being very grateful for the existence of -Werror=format (and > frustrated that __attribute__((format(..))) is as limited as it is :). > > I’m not sure exactly what form support for formatted data in interpolated > strings would take in Swift, but it’s certainly one of the things I find > myself actively missing on a regular basis, and I do have some ideas on how > to go about it, if it isn’t already under discussion/development. > > -- Gwynne Raskind > > > _______________________________________________ > swift-evolution mailing list > swift-evolution@swift.org > https://lists.swift.org/mailman/listinfo/swift-evolution > _______________________________________________ swift-evolution mailing list swift-evolution@swift.org https://lists.swift.org/mailman/listinfo/swift-evolution