http://dev.clojure.org/jira This file is an XML representation of an issue en-us 4.4 649 25-07-2011 http://dev.clojure.org/jira/browse/CLJ-1025 Clojure <p>see: <a href="https://groups.google.com/d/topic/clojure/Kl3WVtEE3FY/discussion">https://groups.google.com/d/topic/clojure/Kl3WVtEE3FY/discussion</a></p> <p>\x.. characters (which are the same as \u00.. characters) are produced by some systems. in particular clojurescript </p> <p>Inability to read these characters hinders data interchange</p> <p>After a quick look, I believe this capability can be easily introduced by adding a case to this <br/> <a href="https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/LispReader.java#L445">https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/LispReader.java#L445</a> function.<br/> Mirroring 'u' case and reading only 2 chars.</p> All CLJ-1025

Enable support for \x.. escaped characters.

Enhancement Minor Closed Declined Unassigned Dave Sann Fri, 13 Jul 2012 22:35:59 -0500 Fri, 19 Oct 2012 19:59:47 -0500 Fri, 19 Oct 2012 13:55:36 -0500 Release 1.4 1 4 <p>Thanks for the patch, Dave. It is Rich Hickey's policy only to include code in Clojure written by those who have signed a Contributor Agreement (CA). See here for more details: <a href="http://clojure.org/contributing">http://clojure.org/contributing</a> Have you signed one, or were considering it?</p> <p>Can someone find some documentation or spec somewhere that defines this \x.. format?</p> <p>It is definitely different than the \x{...} syntax that exists in Perl, which permits one to insert an arbitrary Unicode character code point into a string (note: even supplementary ones that don't fit into a single UTF-16 code unit, as Java's and Clojure's \u.... is restricted to). <a href="http://perldoc.perl.org/perlunicode.html#Effects-of-Character-Semantics">http://perldoc.perl.org/perlunicode.html#Effects-of-Character-Semantics</a></p> <p><a href="http://es5.github.com/x7.html#x7.8.4">http://es5.github.com/x7.html#x7.8.4</a></p> <p>I am happy to sign the CA in principle. Just need to read and understand any implications for me.</p> <p>CA will be with you shortly.</p> <p>Can this go into 1.5?</p> <p>I'm hitting this now as well. But, adding support for JavaScript's flavour of <tt>\x..</tt> escapes to the Clojure reader makes no sense to me. If escapes are to be used, then the <tt>\u....</tt> format seems preferable (it supersets <tt>\x..</tt>).</p> <p>However, all of the readers in play (Clojure reader, ClojureScript reader, edn) all play nice with Unicode, so there's no reason to be escaping anything except for <tt>\t</tt>, <tt>\n</tt>, and so on.</p> <p>It looks like tweaking cljs' string implementations of <tt>IPrintWithWriter</tt> and <tt>IPrintable</tt> so that only those characters are escaped would be fairly easy. Right now, they're using <tt>goog.string.escape</tt>, which "encloses a string in double quotes and escapes characters so that the string is a valid JS string"; whatever escaping is appropriate for a "valid JavaScript string" seems irrelevant to what e.g. <tt>pr-str</tt> should produce.</p> <p>I propose closing this ticket and moving the party to CLJS.</p> <p>Following Chas's lead and closing this one. \x doesn't appear in the JSON spec, and a quick search of StackOverflow shows people stumbling over it from a bunch of other language platforms. I think we should root it out of ClojureScript.</p> <p>Great, I'll open a CLJS ticket with a patch tonight or tomorrow.</p> <p>Re: "no reason to be escaping anything except for \t, \n": sometimes it is difficult or impossible to transmit all of Unicode (e.g. sending non-Character codepoints through XDomainRequest, or sending U+0000/U+FFFE/U+FFFF through many XHR implementations), so it might be nice to have an ASCII-only printing mode. Probably for another ticket, though.</p> <p>Here's the new ticket: <a href="http://dev.clojure.org/jira/browse/CLJS-400">http://dev.clojure.org/jira/browse/CLJS-400</a></p> <p>@Ivan: I agree that options in this area would be good. There are a lot of edge cases where the defaults aren't right (e.g. I think escaping all nonprintables is a no-brainer for readably-printed strings).</p> <p>I suspect planning out such details should probably happen <span class="error">&#91;here&#93;</span>(<a href="http://dev.clojure.org/pages/viewpage.action?pageId=4063586">http://dev.clojure.org/pages/viewpage.action?pageId=4063586</a>) or <span class="error">&#91;here&#93;</span>(<a href="https://github.com/edn-format/edn/issues">https://github.com/edn-format/edn/issues</a>).</p> Approval Not Approved Global Rank Patch Code and Test