lib/editor/htmlarea/plugins/SpellChecker/readme-tech.html

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   3   <head>
   4     <title>HTMLArea Spell Checker</title>
   5   </head>
   6
   7   <body>
   8     <h1>HTMLArea Spell Checker</h1>
   9
  10     <p>The HTMLArea Spell Checker subsystem consists of the following
  11       files:</p>
  12
  13     <ul>
  14
  15       <li>spell-checker.js &mdash; the spell checker plugin interface for
  16         HTMLArea</li>
  17
  18       <li>spell-checker-ui.html &mdash; the HTML code for the user
  19         interface</li>
  20
  21       <li>spell-checker-ui.js &mdash; functionality of the user
  22         interface</li>
  23
  24       <li>spell-checker-logic.cgi &mdash; Perl CGI script that checks a text
  25         given through POST for spelling errors</li>
  26
  27       <li>spell-checker-style.css &mdash; style for mispelled words</li>
  28
  29       <li>lang/en.js &mdash; main language file (English).</li>
  30
  31     </ul>
  32
  33     <h2>Process overview</h2>
  34
  35     <p>
  36       When an end-user clicks the "spell-check" button in the HTMLArea
  37       editor, a new window is opened with the URL of "spell-check-ui.html".
  38       This window initializes itself with the text found in the editor (uses
  39       <tt>window.opener.SpellChecker.editor</tt> global variable) and it
  40       submits the text to the server-side script "spell-check-logic.cgi".
  41       The target of the FORM is an inline frame which is used both to
  42       display the text and correcting.
  43     </p>
  44
  45     <p>
  46       Further, spell-check-logic.cgi calls Aspell for each portion of plain
  47       text found in the given HTML.  It rebuilds an HTML file that contains
  48       clear marks of which words are incorrect, along with suggestions for
  49       each of them.  This file is then loaded in the inline frame.  Upon
  50       loading, a JavaScript function from "spell-check-ui.js" is called.
  51       This function will retrieve all mispelled words from the HTML of the
  52       iframe and will setup the user interface so that it allows correction.
  53     </p>
  54
  55     <h2>The server-side script (spell-check-logic.cgi)</h2>
  56
  57     <p>
  58       <strong>Unicode safety</strong> &mdash; the program <em>is</em>
  59       Unicode safe.  HTML entities are expanded into their corresponding
  60       Unicode characters.  These characters will be matched as part of the
  61       word passed to Aspell.  All texts passed to Aspell are in Unicode
  62       (when appropriate).  However, Aspell seems to not support Unicode
  63       yet (<a
  64         href="http://mail.gnu.org/archive/html/aspell-user/2000-11/msg00007.html">thread concerning Aspell and Unicode</a>).
  65       This mean that words containing Unicode
  66       characters that are not in 0..255 are likely to be reported as "mispelled" by Aspell.
  67     </p>
  68
  69     <p>
  70       I digged the Net for a couple of hours today and I can't seem to find
  71       any open-source spell checker that has Unicode support.  For this
  72       reason we keep using Aspell, because it also seems to have the
  73       best suggestions engine.  Unicode support will eventually be
  74       implemented in Aspell.  <a href="mailto:kevin@atkinson.dhs.org">Email
  75         Kevin Atkinson</a> (Aspell author and maintainer) about this ;-)
  76     </p>
  77
  78     <p>
  79       The Perl Unicode manual (man perluniintro) states:
  80     </p>
  81
  82     <blockquote>
  83       <em>
  84         Starting from Perl 5.6.0, Perl has had the capacity to handle Unicode
  85         natively.  Perl 5.8.0, however, is the first recommended release for
  86         serious Unicode work.  The maintenance release 5.6.1 fixed many of the
  87         problems of the initial Unicode implementation, but for example regular
  88         expressions still do not work with Unicode in 5.6.1.
  89       </em>
  90     </blockquote>
  91
  92     <p>In other words, do <em>not</em> assume that this script is
  93       Unicode-safe on Perl interpreters older than 5.8.0.</p>
  94
  95     <p>The following Perl modules are required:</p>
  96
  97     <ul>
  98       <li><a href="http://search.cpan.org/search?query=Text%3A%3AAspell&mode=all" target="_blank">Text::Aspell</a></li>
  99       <li><a href="http://search.cpan.org/search?query=HTML%3A%3AParser&mode=all" target="_blank">HTML::Parser</a></li>
 100       <li><a href="http://search.cpan.org/search?query=HTML%3A%3AEntities&mode=all" target="_blank">HTML::Entities</a></li>
 101       <li><a href="http://search.cpan.org/search?query=CGI&mode=all" target="_blank">CGI</a></li>
 102     </ul>
 103
 104     <p>Of these, only Text::Aspell might need to be installed manually.  The
 105       others are likely to be available by default in most Perl distributions.</p>
 106
 107     <hr />
 108     <address><a href="http://students.infoiasi.ro/~mishoo/">Mihai Bazon</a></address>
 109 <!-- Created: Thu Jul 17 13:22:27 EEST 2003 -->
 110 <!-- hhmts start -->
 111 Last modified on Sun Aug 10 12:28:24 2003
 112 <!-- hhmts end -->
 113 <!-- doc-lang: English -->
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