.. doctest docs/specs/i18n.rst
.. _book.specs.i18n:

====================
Internationalization
====================


The :func:`lazy_format` function
================================

Lino has a function :func:`lino.core.utils.lazy_format` which we
sometimes use. Here is an example.

>>> from lino import startup
>>> startup('lino_book.projects.min2.settings.demo')
>>> from lino.core.utils import lazy_format
>>> from lino.api import dd, rt, _
>>> M = rt.models.cal.Event
>>> s = lazy_format(
...   _("Only for {model} instances."),
...   model=M._meta.verbose_name)
>>> print(s)
Only for Calendar entry instances.
>>> with dd.translation.override('de'):
...     print(s)
Only for Kalendereintrag instances.

Note that we care only for the "Calendar entry" text. The surrounding
text `Only for {model} instances.` is not translated to German because
it is a fictive example of a translatable string for which there is no
translation.

See also `Django ticket #14174
<https://code.djangoproject.com/ticket/14174>`__.