Translation classes are what actually implement the translation of
original source file message strings to translated message strings.
The base class used by all translation classes is
NullTranslations; this provides the basic interface you can use
to write your own specialized translation classes. Here are the
methods of NullTranslations:
__init__(
[fp])
Takes an optional file object fp, which is ignored by the base
class. Initializes ``protected'' instance variables _info and
_charset which are set by derived classes, as well as _fallback,
which is set through add_fallback. It then calls
self._parse(fp) if fp is not None.
_parse(
fp)
No-op'd in the base class, this method takes file object fp, and
reads the data from the file, initializing its message catalog. If
you have an unsupported message catalog file format, you should
override this method to parse your format.
add_fallback(
fallback)
Add fallback as the fallback object for the current translation
object. A translation object should consult the fallback if it cannot
provide a translation for a given message.
gettext(
message)
If a fallback has been set, forward gettext() to the fallback.
Otherwise, return the translated message. Overridden in derived classes.
lgettext(
message)
If a fallback has been set, forward lgettext() to the fallback.
Otherwise, return the translated message. Overridden in derived classes.
New in version 2.4.
ugettext(
message)
If a fallback has been set, forward ugettext() to the fallback.
Otherwise, return the translated message as a Unicode string.
Overridden in derived classes.
ngettext(
singular, plural, n)
If a fallback has been set, forward ngettext() to the fallback.
Otherwise, return the translated message. Overridden in derived classes.
New in version 2.3.
lngettext(
singular, plural, n)
If a fallback has been set, forward ngettext() to the fallback.
Otherwise, return the translated message. Overridden in derived classes.
New in version 2.4.
ungettext(
singular, plural, n)
If a fallback has been set, forward ungettext() to the fallback.
Otherwise, return the translated message as a Unicode string.
Overridden in derived classes.
New in version 2.3.
info(
)
Return the ``protected'' _info variable.
charset(
)
Return the ``protected'' _charset variable.
output_charset(
)
Return the ``protected'' _output_charset variable, which
defines the encoding used to return translated messages.
New in version 2.4.
set_output_charset(
charset)
Change the ``protected'' _output_charset variable, which
defines the encoding used to return translated messages.
New in version 2.4.
install(
[unicode
[, names]])
If the unicode flag is false, this method installs
self.gettext() into the built-in namespace, binding it to
"_". If unicode is true, it binds self.ugettext()
instead. By default, unicode is false.
If the names parameter is given, it must be a sequence containing
the names of functions you want to install in the builtin namespace in
addition to _(). Supported names are 'gettext' (bound
to self.gettext() or self.ugettext() according to the
unicode flag), 'ngettext' (bound to self.ngettext()
or self.ungettext() according to the unicode flag),
'lgettext' and 'lngettext'.
Note that this is only one way, albeit the most convenient way, to
make the _ function available to your application. Because it
affects the entire application globally, and specifically the built-in
namespace, localized modules should never install _.
Instead, they should use this code to make _ available to
their module:
import gettext
t = gettext.translation('mymodule', ...)
_ = t.gettext
This puts _ only in the module's global namespace and so
only affects calls within this module.
Changed in version 2.5:
Added the names parameter.
