Ubuntu Manpage: Sympa::Language - Handling languages and locales

NAME

       Sympa::Language - Handling languages and locales

SYNOPSIS

         use Sympa::Language;
         my $language = Sympa::Language->instance;
         $language->set_lang('zh-TW', 'zh', 'en');

         print $language->gettext('Lorem ipsum dolor sit amet.');

DESCRIPTION

This package provides interfaces for i18n (internationalization) of Sympa.

The language tags are used to determine each language. A language tag consists of one or
more subtags: language, script, region and variant. Below are some examples.

• "ar" - Arabic language

• "ain" - Ainu language

• "pt-BR" - Portuguese language in Brazil

• "be-Latn" - Belarusian language in Latin script

• "ca-ES-valencia" - Valencian variant of Catalan

Other two sorts of identifiers are derived from language tags: gettext locales and POSIX
locales.

The gettext locales determine each translation catalog. It consists of one to three
parts: language, territory and modifier. For example, their equivalents of language tags
above are "ar", "ain", "pt_BR", "be@latin" and "ca_ES@valencia", respectively.

The POSIX locales determine each locale. They have similar forms to gettext locales and
are used by this package internally.

Functions
Manipulating language tags

canonic_lang ( $lang )
Function. Canonicalizes language tag according to RFC 5646 (BCP 47) and returns it.

Parameter:

$lang
Language tag or similar thing. Old style "locale" by Sympa (see also
"Compatibility") will also be accepted.

Returns:

Canonicalized language tag. In array context, returns an array "(language, script,
region, variant)". For malformed inputs, returns "undef" or empty array.

See "CAVEATS" about details on format.

implicated_langs ( $lang, ... )
Function. Gets a list of each language $lang itself and its "super" languages. For
example: If 'tyv-Latn-MN' is given, this function returns "('tyv-Latn-MN', 'tyv-Latn',
'tyv')".

Parameters:

$lang, ...
Language tags or similar things. They will be canonicalized by "canonic_lang"()
and malformed inputs will be ignored.

Returns:

A list of implicated languages, if any. If no $lang arguments were given, this
function will die.

lang2locale ( $lang )
Function, internal use. Convert language tag to gettext locale name (see also "Native
language support (NLS)"). This function may be useful if you want to know internal
information such as name of catalog file.

Parameter:

$lang
Language tag or similar thing.

Returns:

The gettext locale name. For malformed inputs returns "undef".

negotiate_lang ( $string, $lang, ... )
Function. Get the best language according to the content of "Accept-Language:" HTTP
request header field.

Parameters:

$string
Content of the header. If it is false value, '*' is assumed.

$lang, ...
Acceptable languages.

Returns:

The best language or, if negotiation failed, "undef".

Compatibility

As of Sympa 6.2b, language tags are used to specify languages along with locales. Earlier
releases used POSIX locale names.

These functions are used to migrate data structures and configurations of earlier
versions.

lang2oldlocale ( $lang )
Function. Convert language tag to old-style "locale".

Parameter:

$lang
Language tag or similar thing.

Returns:

Old-style "locale". If corresponding locale could not be determined, returns "undef".

Note: In earlier releases this function was named Lang2Locale() (don't confuse with
"lang2locale"()).

Methods
instance ( )
Constructor. Gets the singleton instance of Sympa::Language class.

Getting/setting language context

push_lang ( [ $lang, ... ] )
Instance method. Set current language by "set_lang"() keeping the previous one; it
can be restored with "pop_lang"().

Parameter:

$lang, ...
Language tags or similar things.

Returns:

Always 1.

pop_lang
Instance method. Restores previous language.

Parameters:

None.

Returns:

Always 1.

set_lang ( [ $lang, ... ] )
Instance method. Sets current language along with translation catalog, and POSIX
locale if possible.

Parameter:

$lang, ...
Language tags or similer things. Old style "locale" by Sympa (see also
"Compatibility") will also be accepted. If multiple tags are specified, this
function trys each of them in order.

Note that 'en' will always succeed. Thus, putting it at the end of argument list
may be useful.

Returns:

Canonic language tag actually set or, if no usable catalogs were found, "undef". If
no arguments are given, do nothing and returns "undef".

Note that the language actually set may not be identical to the parameter $lang, even
when latter has been canonicalized.

The language tag 'en' is special: It is used to set 'C' locale and will succeed
always.

Note: This function of Sympa 6.2a or earlier returned old style "locale" names.

native_name ( )
Instance method. Get the name of the language, ie the one defined in the catalog.

Parameters:

None.

Returns:

Name of the language in native notation. If it was not found, returns an empty string
''.

Note: The name is the content of "Language-Team:" field in the header of catalog.

get_lang ()
Instance method. Get current language tag.

Parameters:

None.

Returns:

Current language. If it is not known, returns default language tag.

Native language support (NLS)

dgettext ( $domain, $msgid )
Instance method. Returns the translation of given string using NLS catalog in domain
$domain. Note that "set_lang"() must be called in advance.

Parameter:

$domain
gettext domain.

$msgid
gettext message ID.

Returns:

Translated string or, if it wasn't found, original string.

gettext ( $msgid )
Instance method. Returns the translation of given string using current NLS catalog.
Note that "set_lang"() must be called in advance.

Parameter:

$msgid
gettext message ID.

Returns:

Translated string or, if it wasn't found, original string.

If special argument '_language_' is given, returns the name of language in native form
(See native_name()). For argument '' returns empty string.

gettext_sprintf ( $format, $args, ... )
Instance method. Internationalized sprintf(). At first, translates $format argument
using "gettext"(). Then returns formatted string by remainder of arguments.

This is equivalent to "sprintf( gettext($format), $args, ... )" with appropriate POSIX
locale if possible.

Parameters:

$format
Format string. See also "sprintf" in perlfunc.

$args, ...
Arguments fed to sprintf().

Returns:

Translated and formatted string.

gettext_strftime ( $format, $args, ... )
Instance method. Internationalized strftime(). At first, translates $format argument
using "gettext"(). Then returns formatted date/time by remainder of arguments.

If appropriate POSIX locale is not available, parts of result (names of days, months
etc.) will be taken from the catalog.

Parameters:

$format
Format string. See also "strftime" in POSIX.

$args, ...
Arguments fed to POSIX::strftime().

Returns:

Translated and formatted string.

maketext ( $textdomain, $template, $args, ... )
Instance method. At first, translates $template argument using "gettext"(). Then
replaces placeholders (%1, %2, ...) in template with arguments.

Numeric arguments will be formatted using appropriate locale, if any: Typically, the
decimal point specific to each locale may be used.

Parameters:

$textdomain
NLS domain to be used for searching catalogs.

$template
Template string which may include placeholders.

$args, ...
Arguments corresponding to placeholders.

Returns:

Translated and replaced string.

Note:

Calls of "gettext"(), "gettext_sprintf"() and "gettext_strftime"() are extracted during
packaging process and are added to translation catalog.

CAVEATS

       •   We impose some restrictions and modifications to the format described in BCP 47:
           language extension subtags won't be supported; if script and variant subtags co-exist,
           latter will be ignored; the first one of multiple variant subtags will be used; each
           variant subtag may be longer than eight characters; extension subtags are not
           supported.

       •   Since catalogs for "zh", "zh-Hans" or "zh-Hant" may not be provided, "set_lang"() will
           choose approximate catalogs for these tags.

HISTORY

       Language module supporting multiple languages by single installation and using NLS catalog
       in msgcat format appeared on Sympa 3.0a.

       Sympa 4.2b.3 adopted gettext portable object (PO) catalog and POSIX locale.

       On Sympa 6.2, rewritten module Sympa::Language adopted BCP 47 language tag to determine
       language context, and installing POSIX locale became optional.

NAME

SYNOPSIS

DESCRIPTION

CAVEATS

SEE ALSO

HISTORY