language agnostic - Fully correct Unicode visual string reversal -


[inspired largely trying explain problems character encoding independent character swap, these other questions neither of contain complete answer: how reverse unicode string, how reversed string (unicode safe)]

doing visual string reversal in unicode harder looks. in storage format other utf-32 have pay attention codepoint boundaries rather going byte-by-byte. that's not enough, because of combining glyphs; spec has concept of "grapheme cluster" that's closer basic unit want reversing. that's still not enough; there sorts of special case characters, bidi overrides , final forms, have fixed up.

this pseudo-algorithm handles easy cases know about:

  1. segment string alternating list of words , word-separators (some word-separators may empty string)
  2. reverse order of list.
  3. for each string in list:
    1. segment string grapheme clusters.
    2. reverse order of grapheme clusters.
    3. check initial , final cluster in reversed sequence; base characters may need reassigned correct form (e.g. if u+05db hebrew letter kaf @ end of sequence needs become u+05da hebrew letter final kaf, , vice versa)
    4. join sequence string.
  4. recombine list of reversed words produce final reversed string.

... doesn't handle bidi overrides , i'm sure there's stuff don't know about, well. can fill in gaps?


Comments

Post a Comment

Popular posts from this blog

SPSS keyboard combination alters encoding -

my question not have programming practical issue on spss. accident keyword combination cannot remember because did not intend press changed encoding in spss , text in data in different language english shown small boxes. nevertheless, when kind of analysis performed different language text shown in output. does know reason? tried change encoding did not produce result. first, @ edit > options , see whether setting unicode or locale. might fix it. if have text in multiple languages, want unicode. otherwise, may have specific locale set wrong. can change set locale, need know locale want use.
Read more

Add new record to the table by click on the button in Microsoft Access -

in ms access form want implement separate button, adds new record table. in order added button , attached button event: private sub btnaddrec_click() refresh codecontextobject on error resume next docmd.gotorecord , , acnewrec if err.number <> 0 btnaddrec.enabled = false end if end end sub everything ok when open window , click btnaddrec button, problem when first of perform navigation through existed records , after click on button. got runtime error: 2105: «you can't go specified record. may @ end of recordset» . how solve issue, need have ability add new record on click on specific button, no matter, have walked or not walked through records before. thanks. i created simple form field call description (and autonumber) , created button code follows click event. filled number of records , navigated through them, clicked addnewrec button. form navigated new record without issues. able click addnewrec button directly after
Read more

CSS3 Transition to highlight new elements created in JQuery -

i want use css3 color transition apply highlight-fading color effect (yellow transparent) new elements appended markup using jquery. css #content div { background-color:transparent; -moz-transition:background-color 2s; -webkit-transition:background-color 2s; -o-transition:background-color 2s; transition:background-color 2s; } #content div.new { background-color:yellow; } html <div id="content"></div> <a id="add-element" href="#">add new element</a> js $('#add-element').click(function() { var newelement = $('<div class="new">new element</div>'); $('#content').append(newelement); newelement.removeclass('new'); }); when click link, new element created. class "new" (background color yellow) , it's appended html markup. should able remove "new" class trigger background color transition transparent (or whate
Read more