From: Kenichi Handa Date: Wed, 10 Sep 2003 23:42:37 +0000 (+0000) Subject: *** empty log message *** X-Git-Tag: emacs-pretest-23.0.90~8295^2~1852 X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=54ce67a02e95247d6a40cb15c9649533ef339c9e;p=emacs.git *** empty log message *** --- diff --git a/README.unicode b/README.unicode new file mode 100644 index 00000000000..3c20084d660 --- /dev/null +++ b/README.unicode @@ -0,0 +1,129 @@ + -*-mode: text; coding: latin-1;-*- + +Problems, fixmes and other issues in the emacs-unicode branch +------------------------------------------------------------- + +Notes by fx to record various things of variable importance. handa +needs to check them -- don't take too seriously, especially with +regard to completeness. + +_Do take seriously that you don't want this branch unless you're +actually working on it; you risk your data by actually using it._ If +you just want to edit Unicode and/or unify iso-8859 et al, see the +existing support and the extra stuff at +, mostly now in the CVS trunk. +(Editing support is mostly orthogonal to the internal representation.) + + * SINGLE_BYTE_CHAR_P returns true for Latin-1 characters, which has + undesirable effects. E.g.: + (multibyte-string-p (let ((s "x")) (aset s 0 ?£) s)) => nil + (multibyte-string-p (concat [?£])) => nil + (text-char-description ?£) => "M-#" + + These examples are all fixed by the change of 2002-10-14, but + there still exist questionalble SINGLE_BYTE_CHAR_P in the + code. + + * Rationalize character syntax and its relationship to the Unicode + database. (Applies mainly to symbol an punctuation syntax.) + + * Fontset handling and customization needs work. We want to relate + fonts to scripts, probably based on the Unicode blocks. The + presence of small-repertoire 10646-encoded fonts in XFree 4 is a + pain, not currently worked round. + + With the change on 2002-07-26, multiple fonts can be + specified in a fontset for a specific range of characters. + Each range can also be specified by script. Before using + ISO10646 fonts, Emacs checks their repertories to avoid such + fonts that don't have a glyph for a specific character. + + * Work is also needed on charset and coding system priorities. + + * The relevant bits of latin1-disp.el need porting (and probably + re-naming/updating). See also cyril-util.el. + + * Quail files need more work now the encoding is irrelevant. + + * What to do with the old coding categories stuff? + + * The preferred-coding-system property of charsets should probably be + junked unless it can be made more useful now. + + * find-multibyte-characters needs looking at. + + * Implement Korean cp949/UHC, BIG5-HKSCS and any other important missing + charsets. + + * Check up on definition of alternativnj. + + * Lazy-load tables for unify-charset somehow? + + Actually, Emacs clear out all charset maps and unify-map just + before dumping, and their are loaded again on demand the + dumped emacs. But, those maps (char tables) generated while + temacs is running can't be get rid of from the dumped emacs. + + * Translation tables for {en,de}code currently aren't supported. + + This should be fixed by the changes of 2002-10-14. + + * Defining CCL coding systems currently doesn't work. + + This should be fixed by the changes of 2003-01-30. + + * iso-2022 charsets get unified on i/o. + + With the change on 2003-01-06, decoding routines put `charset' + property to decoded text, and iso-2022 encoder pay attention + to it. Thus, for instance, reading and writing by + iso-2022-7bit preserve the original designation sequences. + The property name `preferred-charset' may be better? + + We may have to utilize this property to decide a font. + + * Revisit locale processing: look at treating the language and + charset parts separately. (Language should affect things like + speling and calendar, but that's not a Unicode issue.) + + * Handle Unicode combining characters usefully, e.g. diacritics, and + handle more scripts specifically (à la Devanagari). There are + issues with canonicalization. + + * Bidi is a separate issue with no support currently. + + * We need tabular input methods, e.g. for maths symbols. (Not + specific to Unicode.) + + * Need multibyte text in menus, e.g. for the above. (Not specific to + Unicode.) + + * There's currently no support for Unicode normalization. + + * Populate char-width-table correctly for Unicode chanaracters and + worry about what happens when double-width charsets covering + non-CJK characters are unified. + + * Emacs 20/21 .elc files are currently not loadable. It may or may + not be possible to do this properly. + + With the change on 2002-07-24, elc files generated by Emacs + 20.3 and later are correctly loaded (including those + containing multibyte characters and compressed). But, elc + files generated by 20.2 and the primer are still not loadable. + Is it really worth working on it? + + * Rmail won't work with non-ASCII text. Encoding issues for Babyl + files need sorting out, but rms says Babyl will go before this is + released. + + * Gnus still needs some attention, and we need to get changes + accepted by Gnus maintainers... + + * There are type errors lurking, e.g. in + Fcheck_coding_systems_region. Define ENABLE_CHECKING to find them. + + * You can grep the code for lots of fixmes. + + * Old auto-save files, and similar files, such as Gnus drafts, + containing non-ASCII characters probably won't be re-read correctly.