|
74
|
1 .. -*- mode: rst; encoding: utf-8 -*-
|
|
|
2
|
|
|
3 =============================
|
|
|
4 Support Classes and Functions
|
|
|
5 =============================
|
|
|
6
|
|
|
7 .. contents:: Contents
|
|
|
8 :depth: 2
|
|
|
9 .. sectnum::
|
|
|
10
|
|
|
11
|
|
|
12 The ``babel.support`` modules contains a number of classes and functions that
|
|
|
13 can help with integrating Babel, and internationalization in general, into your
|
|
|
14 application or framework. The code in this module is not used by Babel itself,
|
|
|
15 but instead is provided to address common requirements of applications that
|
|
|
16 should handle internationalization.
|
|
|
17
|
|
|
18
|
|
|
19 ---------------
|
|
|
20 Lazy Evaluation
|
|
|
21 ---------------
|
|
|
22
|
|
|
23 One such requirement is lazy evaluation of translations. Many web-based
|
|
|
24 applications define some localizable message at the module level, or in general
|
|
|
25 at some level where the locale of the remote user is not yet known. For such
|
|
|
26 cases, web frameworks generally provide a "lazy" variant of the ``gettext``
|
|
|
27 functions, which basically translates the message not when the ``gettext``
|
|
|
28 function is invoked, but when the string is accessed in some manner.
|
|
|
29
|
|
|
30
|
|
|
31 ---------------------------
|
|
|
32 Extended Translations Class
|
|
|
33 ---------------------------
|
|
|
34
|
|
|
35 Many web-based applications are composed of a variety of different components
|
|
|
36 (possibly using some kind of plugin system), and some of those components may
|
|
|
37 provide their own message catalogs that need to be integrated into the larger
|
|
|
38 system.
|
|
|
39
|
|
|
40 To support this usage pattern, Babel provides a ``Translations`` class that is
|
|
|
41 derived from the ``GNUTranslations`` class in the ``gettext`` module. This
|
|
|
42 class adds a ``merge()`` method that takes another ``Translations`` instance,
|
|
|
43 and merges the content of the latter into the main catalog:
|
|
|
44
|
|
|
45 .. code-block:: python
|
|
|
46
|
|
|
47 translations = Translations.load('main')
|
|
|
48 translations.merge(Translations.load('plugin1'))
|
