One point in the design space that the swift language does, which seems intersting at least to me, is to have the notion of a character be backed by a Unicode grapheme cluster, which is a character like sequence of Unicode code points. Would library support for this at all help this discussion or problem?
On Wednesday, March 30, 2016, Brandon Allbery <allber...@gmail.com> wrote: > On Wed, Mar 30, 2016 at 9:50 PM, Manuel M T Chakravarty < > c...@justtesting.org > <javascript:_e(%7B%7D,'cvml','c...@justtesting.org');>> wrote: > >> Firstly, we have >> >> isPrint :: Char -> Bool >> >> Are you saying that this type is wrong? >> >> Secondly, how often do you feed the output of ’show’ to ’read’ in another >> locale versus how often is everybody whose whole life is outside of ASCII >> (i.e., not anglo-centric people) bothered by this shortcoming? (*) >> >> Moreover, the argument on the ticket was that changing the current >> implementation would go against the standard. Now that I am saying, the >> current implementation is not conforming to the standard, the standard >> suddenly doesn’t seem to matter. Personally, I would say, when we wrote >> that standard, we knew what we were doing. >> > > The standard I am aware of is the Report, which deliberately limited the > output to the subset which is guaranteed to be usable in all locales. show > conforms to this; apparently people want it to *not* conform, and in a way > which requires some locale to become the One True Locale. > > isPrint is, as per the language Report, based on what Char is --- which is > Unicode codepoints. Using it for output --- or for input, for that matter > --- gets you into locale issues because nobody anywhere guarantees that > Unicode codepoints that pass isPrint are representable in every locale. > isPrint is not the place to verify that a character can actually be > displayed in the current locale. > > Or have you decided that ghc should require Unicode locales and nothing > but Unicode locales from now on? If so, what do you do when the next issue > comes up, where Unix is UTF8 and Windows is UTF16? > > -- > brandon s allbery kf8nh sine nomine > associates > allber...@gmail.com <javascript:_e(%7B%7D,'cvml','allber...@gmail.com');> > ballb...@sinenomine.net > <javascript:_e(%7B%7D,'cvml','ballb...@sinenomine.net');> > unix, openafs, kerberos, infrastructure, xmonad > http://sinenomine.net >
_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
