NAME
Locale::TextDomain::OO - Perl OO Interface to Uniforum Message Translation
$Id: OO.pm 492 2014-05-10 15:09:58Z steffenw $
$HeadURL: svn+ssh://steffenw@svn.code.sf.net/p/perl-gettext-oo/code/module/trunk/lib/Locale/TextDomain/OO.pm $
VERSION
1.010
Starting with version 1.000 the interface has changed.
DESCRIPTION
This module provides a high-level interface to Perl message translation.
Why a new module?
This module is similar to Locale::TextDomain and Locale::Maketext.
This module is not using/changing any system locale like Locale::TextDomain.
This module has no magic in how to get the language like Locale::Maketext. You decide what you need.
There are some plugins, so it is possible to use the maketext and/or getext style.
Locale::TextDomain::OO has a flexible object oriented interface based on Moo.
Creating the Lexicon and translating are two splitted things. So it is possible to create the lexicon during the initialisation phase. The connection between both is the singleton mechanimsm of the lexicon module.
How to extract?
Use module Locale::TextDomain::OO::Extract. This is a base class for all source scanner to create pot files. Use this base class and give this module the rules or use one of the already exteded classes. Locale::TextDomain::OO::Extract::Perl is a extension for Perl code and so on.
Do not follow the dead end of Locale::Maketext!
What is the problem of?
Locale::Maketext allows 2 plural forms (and zero) only. This is changable, but the developer has to control the plural forms. He is not an omniscient translator.
'quant' inside a phrase is the end of the automatic translation because quant is an 'or'-construct.
begin of phrase [quant,_1,singular,plural,zero] end of phrase
The plural form is allowed after a number, followed by a whitespace, not a non-breaking whitespace.
1 book 2 books
A plural form can not be before a number.
It is 1 book. These are 2 books.
There is no plural form without a number in the phrase.
I like this book. I like these books.
Placeholders are numbered serially. It is difficult to translate this because the sense of the phrase could be lost.
[_1] is a [_2] in [_3]. Erlangen is a town in Bavaria.
But there are lots of modules around Locale::Maketext.
This is the reason for another module to have:
Endless (real: up to 6) plural forms controlled by the translater and not by the developer.
Named placeholders.
More informations
Run the examples of this distribution (folder example).
Overview
Application calls Application calls Application calls
gettext methods getext and maketext methods
| maketext methods |
| | |
v v v
.-----------------------------------------------------------.
| Locale::TextDomain::OO |
| with plugin LanguageOfLanguages |
| with plugins Locale::TextDomain::OO::Plugin::Expand::... |
|-----------------------------------------------------------|
| Gettext |\ /| Maketext |
| Gettext::DomainAndCategory | > and < | Maketext::Loc |
| |/ \| Maketext::Localize |
`-----------------------------------------------------------'
^
|
.--------------------------'-----------------.
| Locale::TextDomain::OO::Singleton::Lexicon |------------------------.
`--------------------------------------------' |
^ |
| |
.--------------------------'-------------------------------. |
| build lexicon using Locale::TextDomain::OO::Lexicon::... | |
|----------------------------------------------------------| |
| Hash | File::MO | File::PO | |
`----------------------------------------------------------' |
^ ^ ^ ^ |
| | | | |
.-----'-----. _____|_____ .-----'----. .-----'----. |
| Perl | /_ _ _ _ _ _\ | mo files |-. | po files |-. |
| data | | | `----------' |-. `----------' |-. |
| structure | | Database | `----------' | `----------' | |
`-----------' `-----------' `----------' `----------' |
^ ^ |
| | |
build using build using |
gettext tools gettext tools |
(not yet implemented) |
.----------------------------------------'
|
v
.------------------------------------------------------------------.
| build JSON lexicon using Locale::TextDomain::OO::Lexicon::ToJSON |
`------------------------------------------------------------------'
|
v
.--------------.
| lexicon.json |
`-------.------'
|
v
.--- not yet implemented --------.
| js/loc.js |
| with plugins js/loc/expand/... |
|--------------------------------|
| gettext.js |
| gettext/domain_and_category.js |
| maketext.js |
| maketext/loc.js |
| maketext/localize.js |
`--------------------------------'
SYNOPSIS
require Locale::TextDomain::OO;
my $loc = Locale::TextDomain::OO->new(
# all parameters are optional
plugins => [ qw(
Expand::Gettext
+My::Special::Plugin
) ],
language => 'de', # default is i-default
category => 'LC_MESSAGES', # default is q{}
domain => 'MyDomain', # default is q{}
filter => sub {
my ($self, $translation_ref) = @_;
# encode if needed
# run a formatter if needed, e.g.
${$translation_ref} =~ s{__ ( .+? ) __}{<b>$1</b>}xmsg;
return;
},
logger => sub {
my ($message, $arg_ref) = @_;
my $type = $arg_ref->{type}; # debug or warn
Log::Log4perl->get_logger(...)->$type($message);
return;
},
);
This configuration would be use Lexicon "de:LC_MESSAGES:MyDomain". That lexicon should be filled with data.
as singleton
Instead of method new call method instance to get a singleton.
my $instance = Locale::TextDomain::OO->instance(
# Same parameters like new,
# Initialization on first call only.
);
$same_instance = Locale::TextDomain::OO->instance;
Attributes handled with plugin Expand::Gettext
This plugin can handle named placeholders like {name}
. For numeric placeholders add attribute :num
. That allows easier automatic translation and to localize numbers. E.g. write {books :num}
to msgid, msgid_plural.
Grammar rules for string placeholders are able to handle affixes. The translation office can add attributes, e.g. {town :accusative}
to msgstr, msgstr[n].
Add the modifier code like that to handle that attributes.
$loc->expand_gettext->modifier_code(
sub {
my ( $value, $attribute ) = @_;
if ( $loc->language eq 'ru' ) {
if ( $attribute eq 'accusative' ) {
...
}
}
elsif ( $loc->language eq 'de' }xms ) {
if ( $attribute eq 'num' ) {
...
$value =~ tr{.,}{,.};
}
}
return $value;
},
);
Localize numbers with plugin Expand::Maketext
Add the code to localize numbers.
$loc->expand_maketext->formatter_code(
sub {
my $value = shift;
if ( $loc->language eq 'de' ) {
...
$value =~ tr{.,}{,.};
}
return $value;
},
);
SUBROUTINES/METHODS
method new
see SYNOPSIS
method instance
When using the singleton mechanism, the object need not be transported through all the subroutines.
Instead of
my $loc = Locale::TextDomain::OO->new(...);
...
$loc->any_method(...);
write
Locale::TextDomain::OO->instance(...);
...
my $loc = Locale::TextDomain::OO->instance;
$loc->any_method(...);
In case of webserver child or similar, set the language for every reqeuest not as parameter of the first instance call.
method language
Set the language an prepare the translation. You know exactly how to set. This module is stupid.
$loc->language( $language );
Get back
$language = $loc->language;
method category
You are able to ignore or set the category. That depends on your project.
$loc->category($category || q{} );
$category = $loc->category;
method domain
You are able to ignore or set the domain. That depends on your project.
$loc->domain($domain || q{} );
$domain = $loc->domain;
method filter
You are allowed to run code after each translation.
$loc->filter( sub {
my ( $self, $translation_ref ) = @_;
# $self is $loc
# manipulate ${$translation_ref}
# do not undef ${$translation_ref}
return;
} );
Switch off the filter
$loc->filter(undef);
method logger
Set the logger
$loc->logger(
sub {
my ($message, $arg_ref) = @_;
my $type = $arg_ref->{type};
Log::Log4perl->get_logger(...)->$type($message);
return;
},
);
$arg_ref contains
object => $loc, # the object itself
type => 'debug', # or 'warn'
event => 'language,selection', # 'language,selection,fallback'
# or 'translation,fallback'
method translate
Do never call that method in your project. This method was called from expand plugins only.
$translation
= $self->translate($msgctxt, $msgid, $msgid_plural, $count, $is_n);
method run_filter
Do never call that method in your project. This method was called from expand plugins only.
$self->filter(\$translation);
EXAMPLE
Inside of this distribution is a directory named example. Read the file README there. Then run the *.pl files.
DIAGNOSTICS
confess
CONFIGURATION AND ENVIRONMENT
none
DEPENDENCIES
Locale::TextDomain::OO::Translator
INCOMPATIBILITIES
not known
BUGS AND LIMITATIONS
In the gettext manual you can read at "15.5.18.9 Bugs, Pitfalls, And Things That Do Not Work" something that is not working with Perl. The examples there are rewritten and explained here.
string interpolation and joined strings
print <<"EOF";
$loc->__(
'The dot operator'
. ' does not work'
. ' here!'
)
Likewise, you cannot @{[ $loc->__('interpolate function calls') ]}
inside quoted strings or quote-like expressions.
EOF
The fist call can not work. Methods are not callable in interpolated strings/"here documents". The . operator is normally not implemented at the extractor. The first parameter of method __ must be a constant.
There is no problem for the second call because the extractor extracts the Perl file as text and did not parse the code.
Regex eval
This example is no problem here, because the file is extracted as text.
s/<!--START_OF_WEEK-->/$loc->__('Sunday')/e;
named placeholders
Method __ is an alias for method __x. But {OPTIONS} is not a placeholder because key "OPTIONS" is not in parameters.
die $loc->__("usage: $0 {OPTIONS} FILENAME...\n");
die $loc->__x("usage: {program} {OPTIONS} FILENAME...\n", program => $0);
SEE ALSO
http://www.gnu.org/software/gettext/manual/gettext.html
http://en.wikipedia.org/wiki/Gettext
http://translate.sourceforge.net/wiki/l10n/pluralforms
http://rassie.org/archives/247 The choice of the right module for the translation.
AUTHOR
Steffen Winkler
LICENSE AND COPYRIGHT
Copyright (c) 2009 - 2014, Steffen Winkler <steffenw at cpan.org>
. All rights reserved.
This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.