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668 lines
26 KiB
HTML
<HTML>
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<!-- This HTML file has been created by texi2html 1.54
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from gettext.texi on 25 January 1999 -->
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<TITLE>GNU gettext utilities - PO Files and PO Mode Basics</TITLE>
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<link href="gettext_3.html" rel=Next>
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<link href="gettext_1.html" rel=Previous>
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<link href="gettext_toc.html" rel=ToC>
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</HEAD>
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<BODY>
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<p>Go to the <A HREF="gettext_1.html">first</A>, <A HREF="gettext_1.html">previous</A>, <A HREF="gettext_3.html">next</A>, <A HREF="gettext_12.html">last</A> section, <A HREF="gettext_toc.html">table of contents</A>.
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<P><HR><P>
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<H1><A NAME="SEC7" HREF="gettext_toc.html#TOC7">PO Files and PO Mode Basics</A></H1>
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<P>
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The GNU <CODE>gettext</CODE> toolset helps programmers and translators
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at producing, updating and using translation files, mainly those
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PO files which are textual, editable files. This chapter stresses
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the format of PO files, and contains a PO mode starter. PO mode
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description is spread throughout this manual instead of being concentrated
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in one place. Here we present only the basics of PO mode.
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</P>
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<H2><A NAME="SEC8" HREF="gettext_toc.html#TOC8">Completing GNU <CODE>gettext</CODE> Installation</A></H2>
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<P>
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Once you have received, unpacked, configured and compiled the GNU
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<CODE>gettext</CODE> distribution, the <SAMP>`make install'</SAMP> command puts in
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place the programs <CODE>xgettext</CODE>, <CODE>msgfmt</CODE>, <CODE>gettext</CODE>, and
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<CODE>msgmerge</CODE>, as well as their available message catalogs. To
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top off a comfortable installation, you might also want to make the
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PO mode available to your GNU Emacs users.
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</P>
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<P>
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During the installation of the PO mode, you might want modify your
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file <TT>`.emacs'</TT>, once and for all, so it contains a few lines looking
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like:
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</P>
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<PRE>
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(setq auto-mode-alist
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(cons '("\\.po[tx]?\\'\\|\\.po\\." . po-mode) auto-mode-alist))
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(autoload 'po-mode "po-mode")
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</PRE>
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<P>
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Later, whenever you edit some <TT>`.po'</TT>, <TT>`.pot'</TT> or <TT>`.pox'</TT>
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file, or any file having the string <SAMP>`.po.'</SAMP> within its name,
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Emacs loads <TT>`po-mode.elc'</TT> (or <TT>`po-mode.el'</TT>) as needed, and
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automatically activates PO mode commands for the associated buffer.
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The string <EM>PO</EM> appears in the mode line for any buffer for
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which PO mode is active. Many PO files may be active at once in a
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single Emacs session.
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</P>
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<P>
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If you are using Emacs version 20 or better, and have already installed
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the appropriate international fonts on your system, you may also manage
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for the these fonts to be automatically loaded and used for displaying
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the translations on your Emacs screen, whenever necessary. For this to
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happen, you might want to add the lines:
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</P>
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<PRE>
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(autoload 'po-find-file-coding-system "po-mode")
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(modify-coding-system-alist 'file "\\.po[tx]?\\'\\|\\.po\\."
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'po-find-file-coding-system)
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</PRE>
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<P>
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to your <TT>`.emacs'</TT> file.
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</P>
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<H2><A NAME="SEC9" HREF="gettext_toc.html#TOC9">The Format of PO Files</A></H2>
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<P>
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A PO file is made up of many entries, each entry holding the relation
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between an original untranslated string and its corresponding
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translation. All entries in a given PO file usually pertain
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to a single project, and all translations are expressed in a single
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target language. One PO file <STRONG>entry</STRONG> has the following schematic
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structure:
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</P>
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<PRE>
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<VAR>white-space</VAR>
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# <VAR>translator-comments</VAR>
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#. <VAR>automatic-comments</VAR>
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#: <VAR>reference</VAR>...
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#, <VAR>flag</VAR>...
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msgid <VAR>untranslated-string</VAR>
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msgstr <VAR>translated-string</VAR>
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</PRE>
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<P>
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The general structure of a PO file should be well understood by
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the translator. When using PO mode, very little has to be known
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about the format details, as PO mode takes care of them for her.
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</P>
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<P>
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Entries begin with some optional white space. Usually, when generated
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through GNU <CODE>gettext</CODE> tools, there is exactly one blank line
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between entries. Then comments follow, on lines all starting with the
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character <KBD>#</KBD>. There are two kinds of comments: those which have
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some white space immediately following the <KBD>#</KBD>, which comments are
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created and maintained exclusively by the translator, and those which
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have some non-white character just after the <KBD>#</KBD>, which comments
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are created and maintained automatically by GNU <CODE>gettext</CODE> tools.
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All comments, of either kind, are optional.
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</P>
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<P>
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After white space and comments, entries show two strings, giving
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first the untranslated string as it appears in the original program
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sources, and then, the translation of this string. The original
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string is introduced by the keyword <CODE>msgid</CODE>, and the translation,
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by <CODE>msgstr</CODE>. The two strings, untranslated and translated,
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are quoted in various ways in the PO file, using <KBD>"</KBD>
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delimiters and <KBD>\</KBD> escapes, but the translator does not really
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have to pay attention to the precise quoting format, as PO mode fully
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intend to take care of quoting for her.
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</P>
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<P>
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The <CODE>msgid</CODE> strings, as well as automatic comments, are produced
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and managed by other GNU <CODE>gettext</CODE> tools, and PO mode does not
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provide means for the translator to alter these. The most she can
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do is merely deleting them, and only by deleting the whole entry.
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On the other hand, the <CODE>msgstr</CODE> string, as well as translator
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comments, are really meant for the translator, and PO mode gives her
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the full control she needs.
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</P>
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<P>
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The comment lines beginning with <KBD>#,</KBD> are special because they are
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not completely ignored by the programs as comments generally are. The
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comma separated list of <VAR>flag</VAR>s is used by the <CODE>msgfmt</CODE>
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program to give the user some better diagnostic messages. Currently
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there are two forms of flags defined:
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</P>
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<DL COMPACT>
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<DT><KBD>fuzzy</KBD>
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<DD>
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This flag can be generated by the <CODE>msgmerge</CODE> program or it can be
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inserted by the translator herself. It shows that the <CODE>msgstr</CODE>
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string might not be a correct translation (anymore). Only the translator
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can judge if the translation requires further modification, or is
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acceptable as is. Once satisfied with the translation, she then removes
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this <KBD>fuzzy</KBD> attribute. The <CODE>msgmerge</CODE> programs inserts this
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when it combined the <CODE>msgid</CODE> and <CODE>msgstr</CODE> entries after fuzzy
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search only. See section <A HREF="gettext_5.html#SEC26">Fuzzy Entries</A>.
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<DT><KBD>c-format</KBD>
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<DD>
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<DT><KBD>no-c-format</KBD>
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<DD>
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These flags should not be added by a human. Instead only the
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<CODE>xgettext</CODE> program adds them. In an automated PO file processing
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system as proposed here the user changes would be thrown away again as
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soon as the <CODE>xgettext</CODE> program generates a new template file.
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In case the <KBD>c-format</KBD> flag is given for a string the <CODE>msgfmt</CODE>
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does some more tests to check to validity of the translation.
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See section <A HREF="gettext_6.html#SEC33">Invoking the <CODE>msgfmt</CODE> Program</A>.
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</DL>
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<P>
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It happens that some lines, usually whitespace or comments, follow the
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very last entry of a PO file. Such lines are not part of any entry,
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and PO mode is unable to take action on those lines. By using the
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PO mode function <KBD>M-x po-normalize</KBD>, the translator may get
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rid of those spurious lines. See section <A HREF="gettext_2.html#SEC12">Normalizing Strings in Entries</A>.
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</P>
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<P>
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The remainder of this section may be safely skipped by those using
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PO mode, yet it may be interesting for everybody to have a better
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idea of the precise format of a PO file. On the other hand, those
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not having GNU Emacs handy should carefully continue reading on.
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</P>
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<P>
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Each of <VAR>untranslated-string</VAR> and <VAR>translated-string</VAR> respects
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the C syntax for a character string, including the surrounding quotes
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and embedded backslashed escape sequences. When the time comes
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to write multi-line strings, one should not use escaped newlines.
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Instead, a closing quote should follow the last character on the
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line to be continued, and an opening quote should resume the string
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at the beginning of the following PO file line. For example:
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</P>
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<PRE>
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msgid ""
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"Here is an example of how one might continue a very long string\n"
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"for the common case the string represents multi-line output.\n"
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</PRE>
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<P>
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In this example, the empty string is used on the first line, to
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allow better alignment of the <KBD>H</KBD> from the word <SAMP>`Here'</SAMP>
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over the <KBD>f</KBD> from the word <SAMP>`for'</SAMP>. In this example, the
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<CODE>msgid</CODE> keyword is followed by three strings, which are meant
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to be concatenated. Concatenating the empty string does not change
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the resulting overall string, but it is a way for us to comply with
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the necessity of <CODE>msgid</CODE> to be followed by a string on the same
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line, while keeping the multi-line presentation left-justified, as
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we find this to be a cleaner disposition. The empty string could have
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been omitted, but only if the string starting with <SAMP>`Here'</SAMP> was
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promoted on the first line, right after <CODE>msgid</CODE>.<A NAME="DOCF1" HREF="gettext_foot.html#FOOT1">(1)</A> It was not really necessary
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either to switch between the two last quoted strings immediately after
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the newline <SAMP>`\n'</SAMP>, the switch could have occurred after <EM>any</EM>
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other character, we just did it this way because it is neater.
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</P>
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<P>
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One should carefully distinguish between end of lines marked as
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<SAMP>`\n'</SAMP> <EM>inside</EM> quotes, which are part of the represented
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string, and end of lines in the PO file itself, outside string quotes,
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which have no incidence on the represented string.
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</P>
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<P>
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Outside strings, white lines and comments may be used freely.
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Comments start at the beginning of a line with <SAMP>`#'</SAMP> and extend
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until the end of the PO file line. Comments written by translators
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should have the initial <SAMP>`#'</SAMP> immediately followed by some white
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space. If the <SAMP>`#'</SAMP> is not immediately followed by white space,
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this comment is most likely generated and managed by specialized GNU
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tools, and might disappear or be replaced unexpectedly when the PO
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file is given to <CODE>msgmerge</CODE>.
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</P>
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<H2><A NAME="SEC10" HREF="gettext_toc.html#TOC10">Main PO mode Commands</A></H2>
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<P>
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After setting up Emacs with something similar to the lines in
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section <A HREF="gettext_2.html#SEC8">Completing GNU <CODE>gettext</CODE> Installation</A>, PO mode is activated for a window when Emacs finds a
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PO file in that window. This puts the window read-only and establishes a
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po-mode-map, which is a genuine Emacs mode, in a way that is not derived
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from text mode in any way. Functions found on <CODE>po-mode-hook</CODE>,
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if any, will be executed.
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</P>
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<P>
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When PO mode is active in a window, the letters <SAMP>`PO'</SAMP> appear
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in the mode line for that window. The mode line also displays how
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many entries of each kind are held in the PO file. For example,
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the string <SAMP>`132t+3f+10u+2o'</SAMP> would tell the translator that the
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PO mode contains 132 translated entries (see section <A HREF="gettext_5.html#SEC25">Translated Entries</A>,
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3 fuzzy entries (see section <A HREF="gettext_5.html#SEC26">Fuzzy Entries</A>), 10 untranslated entries
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(see section <A HREF="gettext_5.html#SEC27">Untranslated Entries</A>) and 2 obsolete entries (see section <A HREF="gettext_5.html#SEC28">Obsolete Entries</A>). Zero-coefficients items are not shown. So, in this example, if
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the fuzzy entries were unfuzzied, the untranslated entries were translated
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and the obsolete entries were deleted, the mode line would merely display
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<SAMP>`145t'</SAMP> for the counters.
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</P>
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<P>
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The main PO commands are those which do not fit into the other categories of
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subsequent sections. These allow for quitting PO mode or for managing windows
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in special ways.
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</P>
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<DL COMPACT>
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<DT><KBD>U</KBD>
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<DD>
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Undo last modification to the PO file.
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<DT><KBD>Q</KBD>
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<DD>
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Quit processing and save the PO file.
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<DT><KBD>q</KBD>
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<DD>
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Quit processing, possibly after confirmation.
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<DT><KBD>O</KBD>
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<DD>
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Temporary leave the PO file window.
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<DT><KBD>?</KBD>
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<DD>
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<DT><KBD>h</KBD>
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<DD>
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Show help about PO mode.
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<DT><KBD>=</KBD>
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<DD>
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Give some PO file statistics.
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<DT><KBD>V</KBD>
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<DD>
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Batch validate the format of the whole PO file.
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</DL>
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<P>
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The command <KBD>U</KBD> (<CODE>po-undo</CODE>) interfaces to the GNU Emacs
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<EM>undo</EM> facility. See section `Undoing Changes' in <CITE>The Emacs Editor</CITE>. Each time <KBD>U</KBD> is typed, modifications which the translator
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did to the PO file are undone a little more. For the purpose of
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undoing, each PO mode command is atomic. This is especially true for
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the <KBD><KBD>RET</KBD></KBD> command: the whole edition made by using a single
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use of this command is undone at once, even if the edition itself
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implied several actions. However, while in the editing window, one
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can undo the edition work quite parsimoniously.
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</P>
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<P>
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The commands <KBD>Q</KBD> (<CODE>po-quit</CODE>) and <KBD>q</KBD>
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(<CODE>po-confirm-and-quit</CODE>) are used when the translator is done with the
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PO file. The former is a bit less verbose than the latter. If the file
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has been modified, it is saved to disk first. In both cases, and prior to
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all this, the commands check if some untranslated message remains in the
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PO file and, if yes, the translator is asked if she really wants to leave
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off working with this PO file. This is the preferred way of getting rid
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of an Emacs PO file buffer. Merely killing it through the usual command
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<KBD>C-x k</KBD> (<CODE>kill-buffer</CODE>) is not the tidiest way to proceed.
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</P>
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<P>
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The command <KBD>O</KBD> (<CODE>po-other-window</CODE>) is another, softer way,
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to leave PO mode, temporarily. It just moves the cursor to some other
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Emacs window, and pops one if necessary. For example, if the translator
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just got PO mode to show some source context in some other, she might
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discover some apparent bug in the program source that needs correction.
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This command allows the translator to change sex, become a programmer,
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and have the cursor right into the window containing the program she
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(or rather <EM>he</EM>) wants to modify. By later getting the cursor back
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in the PO file window, or by asking Emacs to edit this file once again,
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PO mode is then recovered.
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</P>
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<P>
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The command <KBD>h</KBD> (<CODE>po-help</CODE>) displays a summary of all available PO
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mode commands. The translator should then type any character to resume
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normal PO mode operations. The command <KBD>?</KBD> has the same effect
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as <KBD>h</KBD>.
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</P>
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<P>
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The command <KBD>=</KBD> (<CODE>po-statistics</CODE>) computes the total number of
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entries in the PO file, the ordinal of the current entry (counted from
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1), the number of untranslated entries, the number of obsolete entries,
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and displays all these numbers.
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</P>
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<P>
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The command <KBD>V</KBD> (<CODE>po-validate</CODE>) launches <CODE>msgfmt</CODE> in verbose
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mode over the current PO file. This command first offers to save the
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current PO file on disk. The <CODE>msgfmt</CODE> tool, from GNU <CODE>gettext</CODE>,
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has the purpose of creating a MO file out of a PO file, and PO mode uses
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the features of this program for checking the overall format of a PO file,
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as well as all individual entries.
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</P>
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<P>
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The program <CODE>msgfmt</CODE> runs asynchronously with Emacs, so the
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translator regains control immediately while her PO file is being studied.
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Error output is collected in the GNU Emacs <SAMP>`*compilation*'</SAMP> buffer,
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displayed in another window. The regular GNU Emacs command <KBD>C-x`</KBD>
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(<CODE>next-error</CODE>), as well as other usual compile commands, allow the
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translator to reposition quickly to the offending parts of the PO file.
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Once the cursor is on the line in error, the translator may decide on
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any PO mode action which would help correcting the error.
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</P>
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<H2><A NAME="SEC11" HREF="gettext_toc.html#TOC11">Entry Positioning</A></H2>
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<P>
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The cursor in a PO file window is almost always part of
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an entry. The only exceptions are the special case when the cursor
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is after the last entry in the file, or when the PO file is
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empty. The entry where the cursor is found to be is said to be the
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current entry. Many PO mode commands operate on the current entry,
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so moving the cursor does more than allowing the translator to browse
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the PO file, this also selects on which entry commands operate.
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</P>
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<P>
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Some PO mode commands alter the position of the cursor in a specialized
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way. A few of those special purpose positioning are described here,
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the others are described in following sections.
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</P>
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<DL COMPACT>
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<DT><KBD>.</KBD>
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<DD>
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Redisplay the current entry.
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<DT><KBD>n</KBD>
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<DD>
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<DT><KBD>n</KBD>
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<DD>
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Select the entry after the current one.
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<DT><KBD>p</KBD>
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<DD>
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<DT><KBD>p</KBD>
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<DD>
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Select the entry before the current one.
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<DT><KBD><</KBD>
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<DD>
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Select the first entry in the PO file.
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<DT><KBD>></KBD>
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<DD>
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Select the last entry in the PO file.
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<DT><KBD>m</KBD>
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<DD>
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Record the location of the current entry for later use.
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<DT><KBD>l</KBD>
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<DD>
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Return to a previously saved entry location.
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<DT><KBD>x</KBD>
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<DD>
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Exchange the current entry location with the previously saved one.
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</DL>
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<P>
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|
Any GNU Emacs command able to reposition the cursor may be used
|
|
to select the current entry in PO mode, including commands which
|
|
move by characters, lines, paragraphs, screens or pages, and search
|
|
commands. However, there is a kind of standard way to display the
|
|
current entry in PO mode, which usual GNU Emacs commands moving
|
|
the cursor do not especially try to enforce. The command <KBD>.</KBD>
|
|
(<CODE>po-current-entry</CODE>) has the sole purpose of redisplaying the
|
|
current entry properly, after the current entry has been changed by
|
|
means external to PO mode, or the Emacs screen otherwise altered.
|
|
|
|
</P>
|
|
<P>
|
|
It is yet to be decided if PO mode helps the translator, or otherwise
|
|
irritates her, by forcing a rigid window disposition while she
|
|
is doing her work. We originally had quite precise ideas about
|
|
how windows should behave, but on the other hand, anyone used to
|
|
GNU Emacs is often happy to keep full control. Maybe a fixed window
|
|
disposition might be offered as a PO mode option that the translator
|
|
might activate or deactivate at will, so it could be offered on an
|
|
experimental basis. If nobody feels a real need for using it, or
|
|
a compulsion for writing it, we should drop this whole idea.
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|
The incentive for doing it should come from translators rather than
|
|
programmers, as opinions from an experienced translator are surely
|
|
more worth to me than opinions from programmers <EM>thinking</EM> about
|
|
how <EM>others</EM> should do translation.
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|
|
|
</P>
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|
<P>
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|
The commands <KBD>n</KBD> (<CODE>po-next-entry</CODE>) and <KBD>p</KBD>
|
|
(<CODE>po-previous-entry</CODE>) move the cursor the entry following,
|
|
or preceding, the current one. If <KBD>n</KBD> is given while the
|
|
cursor is on the last entry of the PO file, or if <KBD>p</KBD>
|
|
is given while the cursor is on the first entry, no move is done.
|
|
|
|
</P>
|
|
<P>
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|
The commands <KBD><</KBD> (<CODE>po-first-entry</CODE>) and <KBD>></KBD>
|
|
(<CODE>po-last-entry</CODE>) move the cursor to the first entry, or last
|
|
entry, of the PO file. When the cursor is located past the last
|
|
entry in a PO file, most PO mode commands will return an error saying
|
|
<SAMP>`After last entry'</SAMP>. Moreover, the commands <KBD><</KBD> and <KBD>></KBD>
|
|
have the special property of being able to work even when the cursor
|
|
is not into some PO file entry, and one may use them for nicely
|
|
correcting this situation. But even these commands will fail on a
|
|
truly empty PO file. There are development plans for the PO mode for it
|
|
to interactively fill an empty PO file from sources. See section <A HREF="gettext_3.html#SEC16">Marking Translatable Strings</A>.
|
|
|
|
</P>
|
|
<P>
|
|
The translator may decide, before working at the translation of
|
|
a particular entry, that she needs to browse the remainder of the
|
|
PO file, maybe for finding the terminology or phraseology used
|
|
in related entries. She can of course use the standard Emacs idioms
|
|
for saving the current cursor location in some register, and use that
|
|
register for getting back, or else, use the location ring.
|
|
|
|
</P>
|
|
<P>
|
|
PO mode offers another approach, by which cursor locations may be saved
|
|
onto a special stack. The command <KBD>m</KBD> (<CODE>po-push-location</CODE>)
|
|
merely adds the location of current entry to the stack, pushing
|
|
the already saved locations under the new one. The command
|
|
<KBD>r</KBD> (<CODE>po-pop-location</CODE>) consumes the top stack element and
|
|
reposition the cursor to the entry associated with that top element.
|
|
This position is then lost, for the next <KBD>r</KBD> will move the cursor
|
|
to the previously saved location, and so on until no locations remain
|
|
on the stack.
|
|
|
|
</P>
|
|
<P>
|
|
If the translator wants the position to be kept on the location stack,
|
|
maybe for taking a look at the entry associated with the top
|
|
element, then go elsewhere with the intent of getting back later, she
|
|
ought to use <KBD>m</KBD> immediately after <KBD>r</KBD>.
|
|
|
|
</P>
|
|
<P>
|
|
The command <KBD>x</KBD> (<CODE>po-exchange-location</CODE>) simultaneously
|
|
reposition the cursor to the entry associated with the top element of
|
|
the stack of saved locations, and replace that top element with the
|
|
location of the current entry before the move. Consequently, repeating
|
|
the <KBD>x</KBD> command toggles alternatively between two entries.
|
|
For achieving this, the translator will position the cursor on the
|
|
first entry, use <KBD>m</KBD>, then position to the second entry, and
|
|
merely use <KBD>x</KBD> for making the switch.
|
|
|
|
</P>
|
|
|
|
|
|
<H2><A NAME="SEC12" HREF="gettext_toc.html#TOC12">Normalizing Strings in Entries</A></H2>
|
|
|
|
<P>
|
|
There are many different ways for encoding a particular string into a
|
|
PO file entry, because there are so many different ways to split and
|
|
quote multi-line strings, and even, to represent special characters
|
|
by backslashed escaped sequences. Some features of PO mode rely on
|
|
the ability for PO mode to scan an already existing PO file for a
|
|
particular string encoded into the <CODE>msgid</CODE> field of some entry.
|
|
Even if PO mode has internally all the built-in machinery for
|
|
implementing this recognition easily, doing it fast is technically
|
|
difficult. To facilitate a solution to this efficiency problem,
|
|
we decided on a canonical representation for strings.
|
|
|
|
</P>
|
|
<P>
|
|
A conventional representation of strings in a PO file is currently
|
|
under discussion, and PO mode experiments with a canonical representation.
|
|
Having both <CODE>xgettext</CODE> and PO mode converging towards a uniform
|
|
way of representing equivalent strings would be useful, as the internal
|
|
normalization needed by PO mode could be automatically satisfied
|
|
when using <CODE>xgettext</CODE> from GNU <CODE>gettext</CODE>. An explicit
|
|
PO mode normalization should then be only necessary for PO files
|
|
imported from elsewhere, or for when the convention itself evolves.
|
|
|
|
</P>
|
|
<P>
|
|
So, for achieving normalization of at least the strings of a given
|
|
PO file needing a canonical representation, the following PO mode
|
|
command is available:
|
|
|
|
</P>
|
|
<DL COMPACT>
|
|
|
|
<DT><KBD>M-x po-normalize</KBD>
|
|
<DD>
|
|
Tidy the whole PO file by making entries more uniform.
|
|
|
|
</DL>
|
|
|
|
<P>
|
|
The special command <KBD>M-x po-normalize</KBD>, which has no associate
|
|
keys, revises all entries, ensuring that strings of both original
|
|
and translated entries use uniform internal quoting in the PO file.
|
|
It also removes any crumb after the last entry. This command may be
|
|
useful for PO files freshly imported from elsewhere, or if we ever
|
|
improve on the canonical quoting format we use. This canonical format
|
|
is not only meant for getting cleaner PO files, but also for greatly
|
|
speeding up <CODE>msgid</CODE> string lookup for some other PO mode commands.
|
|
|
|
</P>
|
|
<P>
|
|
<KBD>M-x po-normalize</KBD> presently makes three passes over the entries.
|
|
The first implements heuristics for converting PO files for GNU
|
|
<CODE>gettext</CODE> 0.6 and earlier, in which <CODE>msgid</CODE> and <CODE>msgstr</CODE>
|
|
fields were using K&R style C string syntax for multi-line strings.
|
|
These heuristics may fail for comments not related to obsolete
|
|
entries and ending with a backslash; they also depend on subsequent
|
|
passes for finalizing the proper commenting of continued lines for
|
|
obsolete entries. This first pass might disappear once all oldish PO
|
|
files would have been adjusted. The second and third pass normalize
|
|
all <CODE>msgid</CODE> and <CODE>msgstr</CODE> strings respectively. They also
|
|
clean out those trailing backslashes used by XView's <CODE>msgfmt</CODE>
|
|
for continued lines.
|
|
|
|
</P>
|
|
<P>
|
|
Having such an explicit normalizing command allows for importing PO
|
|
files from other sources, but also eases the evolution of the current
|
|
convention, evolution driven mostly by aesthetic concerns, as of now.
|
|
It is easy to make suggested adjustments at a later time, as the
|
|
normalizing command and eventually, other GNU <CODE>gettext</CODE> tools
|
|
should greatly automate conformance. A description of the canonical
|
|
string format is given below, for the particular benefit of those not
|
|
having GNU Emacs handy, and who would nevertheless want to handcraft
|
|
their PO files in nice ways.
|
|
|
|
</P>
|
|
<P>
|
|
Right now, in PO mode, strings are single line or multi-line. A string
|
|
goes multi-line if and only if it has <EM>embedded</EM> newlines, that
|
|
is, if it matches <SAMP>`[^\n]\n+[^\n]'</SAMP>. So, we would have:
|
|
|
|
</P>
|
|
|
|
<PRE>
|
|
msgstr "\n\nHello, world!\n\n\n"
|
|
</PRE>
|
|
|
|
<P>
|
|
but, replacing the space by a newline, this becomes:
|
|
|
|
</P>
|
|
|
|
<PRE>
|
|
msgstr ""
|
|
"\n"
|
|
"\n"
|
|
"Hello,\n"
|
|
"world!\n"
|
|
"\n"
|
|
"\n"
|
|
</PRE>
|
|
|
|
<P>
|
|
We are deliberately using a caricatural example, here, to make the
|
|
point clearer. Usually, multi-lines are not that bad looking.
|
|
It is probable that we will implement the following suggestion.
|
|
We might lump together all initial newlines into the empty string,
|
|
and also all newlines introducing empty lines (that is, for <VAR>n</VAR>
|
|
> 1, the <VAR>n</VAR>-1'th last newlines would go together on a separate
|
|
string), so making the previous example appear:
|
|
|
|
</P>
|
|
|
|
<PRE>
|
|
msgstr "\n\n"
|
|
"Hello,\n"
|
|
"world!\n"
|
|
"\n\n"
|
|
</PRE>
|
|
|
|
<P>
|
|
There are a few yet undecided little points about string normalization,
|
|
to be documented in this manual, once these questions settle.
|
|
|
|
</P>
|
|
<P><HR><P>
|
|
<p>Go to the <A HREF="gettext_1.html">first</A>, <A HREF="gettext_1.html">previous</A>, <A HREF="gettext_3.html">next</A>, <A HREF="gettext_12.html">last</A> section, <A HREF="gettext_toc.html">table of contents</A>.
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|
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