C[omp]ute

From: "andrew cooke" <andrew@...>

Date: Sat, 26 Apr 2008 18:08:47 -0400 (CLT)

Busy day - now have i18n working for Python too.  It's quite cool - uses
Gnu gettext which has made some interesting design decisions.  In
particular, it fails very nicely - at worst, you get the (english) text in
your source file.

Here are my notes:

==Internationalisation (Python)==

* [http://www.gnu.org/software/gettext/manual/gettext.html Gettext manual]
* [http://docs.python.org/lib/module-gettext.html Python docs]

===Create Source===

The simplest approach is to use the library routines in acooke.i18n:

* Within an application, set <code>_</code> globally in the "main" file:

 from acooke.i18n import init_app_i18n
 from acooke.log import init_log
 init_log('appname.ini')
 init_app_i18n('appname')

* Within a library, set <code>_</code> locally within each module:

 from acooke.i18n import init_lib_i18n
 _ = init_lib_i18n('libname')

Then call this function around english text.  Note that <code>%</code>
formatting should be outside the string and use dictionaries (so that the
order can be changed).  For example:

 print _('hello %(name)s') % {'name': 'andrew'}

===Create Templates===

Run the pygettext program to create a ".pot" template based on all the
files in the application:

 rm -f appname.pot
 python /usr/share/doc/packages/python/Tools/i18n/pygettext.py -nvd
appname `find appname -name "*.py"`

===Initialise Translation===

Run the msginit program.  By default this searches for the ".pot" file and
uses the default locale (which means you get an english version for
testing, probably).

 msginit
 ...

At this point you may want to merge in previous work.  This requires
msgmerge (more here....).

===Edit the Translation===

 emacs en_GB.po
'?' for help; enter to edit

===Create the Binary "mo"===

Use /usr/share/doc/packages/python/Tools/i18n/msgfmt.py to generate the
machine readable file.  For example:

 #!/bin/bash
 if [ -z "$1" -o $# -ne 1 ]
 then
   echo 'the first (and only) argument should be the input file'
   echo 'this should look something like en_GB.po'
   exit
 fi
 locale=`echo "$1" | sed -e "s/^\([A-Za-z]*\).*/\\1/"`
 dir="locale/$locale/LC_MESSAGES"
 mkdir -p "$dir"
 python /usr/share/doc/packages/python/Tools/i18n/msgfmt.py -o
"$dir/appname.mo" $1

Andrew