doc/xslt/params/l10n.lang.value.rfc.compliant.xml

   1 <refentry xmlns="http://docbook.org/ns/docbook"
   2           xmlns:xlink="http://www.w3.org/1999/xlink"
   3           xmlns:xi="http://www.w3.org/2001/XInclude"
   4           xmlns:src="http://nwalsh.com/xmlns/litprog/fragment"
   5           xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
   6           version="5.0" xml:id="l10n.lang.value.rfc.compliant">
   7 <refmeta>
   8 <refentrytitle>l10n.lang.value.rfc.compliant</refentrytitle>
   9 <refmiscinfo class="other" otherclass="datatype">boolean</refmiscinfo>
  10 </refmeta>
  11 <refnamediv>
  12 <refname>l10n.lang.value.rfc.compliant</refname>
  13 <refpurpose>Make value of lang attribute RFC compliant?</refpurpose>
  14 </refnamediv>
  15
  16 <refsynopsisdiv>
  17 <src:fragment xml:id="l10n.lang.value.rfc.compliant.frag">
  18 <xsl:param name="l10n.lang.value.rfc.compliant" select="1"/>
  19 </src:fragment>
  20 </refsynopsisdiv>
  21
  22 <refsection><info><title>Description</title></info>
  23
  24 <para>If non-zero, ensure that the values for all <tag class="attribute">lang</tag> attributes in HTML output are RFC
  25 compliant<footnote><para>Section 8.1.1, <link xlink:href="http://www.w3.org/TR/REC-html40/struct/dirlang.html#h-8.1.1">Language Codes</link>, in the HTML 4.0 Recommendation states that:
  26
  27 <blockquote><para>[RFC1766] defines and explains the language codes
  28 that must be used in HTML documents.</para>
  29 <para>Briefly, language codes consist of a primary code and a possibly
  30 empty series of subcodes:
  31
  32 <literallayout class="monospaced">language-code = primary-code ( "-" subcode )*</literallayout>
  33 </para>
  34 <para>And in RFC 1766, <link xlink:href="http://www.ietf.org/rfc/rfc1766.txt">Tags for the Identification
  35 of Languages</link>, the EBNF for "language tag" is given as:
  36
  37 <literallayout class="monospaced">Language-Tag = Primary-tag *( "-" Subtag )
  38 Primary-tag = 1*8ALPHA
  39 Subtag = 1*8ALPHA</literallayout>
  40 </para>
  41 </blockquote>
  42 </para></footnote>.
  43
  44 by taking any underscore characters in any <tag class="attribute">lang</tag> values found in source documents, and
  45 replacing them with hyphen characters in output HTML files. For
  46 example, <literal>zh_CN</literal> in a source document becomes
  47 <literal>zh-CN</literal> in the HTML output form that source.
  48
  49 <note>
  50 <para>This parameter does not cause any case change in <tag class="attribute">lang</tag> values, because RFC 1766
  51 explicitly states that all "language tags" (as it calls them) "are
  52 to be treated as case insensitive".</para>
  53 </note>
  54 </para>
  55
  56 </refsection>
  57 </refentry>