Object::I18n - Internationalize objects


NAME

Object::I18n - Internationalize objects


SYNOPSIS

    package Greeting;
    sub new { my $x = $_[1]; bless \$x; }
    sub greeting { @_ ? ${$_[1]} : (${$_[1]} = $_[2]) }
    use Object::I18n qw(id);
    __PACKAGE__->i18n->storage('Greeting::CDBI::I18n');
    __PACKAGE__->i18n->register('greeting');

    package main;
    my $obj = Greeting->new("Hello, world\n");
    print $obj->greeting;# "Hello, world\n"
    $obj->i18n->language('fr');
    print $obj->greeting;# exception
    $obj->greeting("Bonjour, monde\n");
    print $obj->greeting;# "Bonjour, monde\n"

=cut

my %i18n_object;

sub i18n { my $self = shift; my $class = ref $self || $self; my $i18n = $i18n_object{$class}; return $i18n unless ref $self;

    _prune($i18n->{instance});
    my $oid_method = $i18n->{oid_method};
    my $oid = $self->$oid_method;
    my $instance_i18n = $i18n->{instance}{$oid};

    $i18n->{instance}{$oid} ||= $i18n->_clone($self);
}

sub import { my ($class, %opts) = (@_); my ($pkg) = caller; $class->_init_i18n_object($pkg, %opts); no strict 'refs'; *{ ``$pkg\::i18n'' } = \&i18n; }

sub oid { my $self = shift; my $oid_method = $self->{oid_method}; return $self->{object}->$oid_method; }

sub _prune { my ($instance) = @_; for my $oid (keys %$instance) { next if $instance->{$oid}{object}; delete $instance->{$oid}; } }

sub _clone { my $self = shift; my ($obj) = @_; # XXX - may need deeper cloning than this my $clone = { %$self }; delete $clone->{instance}; delete $clone->{language}; $clone->{object} = $obj; # $clone->{object} will be undef when the object is DESTROYed. weaken($clone->{object}); return bless $clone, __PACKAGE__; }

# The i18n object has these attributes: # class - The package of the class or object # oid_method - A method in ``class'' that returns a unique object id # language - The current language for the class or object # object - The object that contains the i18n object # instance - A hash of i18n instances stored in the class i18n # registered_methods - A hash of overridden methods # sub _init_i18n_object { my $class = shift; my ($pkg, %attrs) = @_; $attrs{oid_method} ||= 'id'; $attrs{storage_class} ||= 'Object::I18n::Storage::MemHash'; croak ``invalid storage_class'' if $attrs{storage_class} =~ /[^\w:]/; eval ``require $attrs{storage_class}; 1'' or die $@;

    my $obj = bless {
        class => $pkg,
        %attrs,
    }, $class;
    $i18n_object{$pkg} = $obj;
}

sub register { my $self = shift; my @methods = @_; my $registered = $self->{registered_methods} ||= {}; my $class = $self->{class} or die ``register must be called as class method''; for my $method (@methods) { croak ``No such method '$method' found for class '$class''' unless my $code = $class->can($method); $registered->{$method} = $code; no strict 'refs'; no warnings 'redefine'; *{ ``$class\::$method'' } = sub { my $self = shift; return $self->$code(@_) unless $self->i18n->language;

            my $storage_class = $self->i18n->{storage_class};
            my $storage = $storage_class->new($self, $method)
                or croak "Could not create instance of '$storage_class'"
                         . "for '$method'";
            return $storage->store(@_) if @_;
            return $storage->fetch;
        };
    }
    keys %$registered;
}

sub storage_class { my $self = shift; $self->{storage_class}; }

sub registered_methods { my $self = shift; keys %{ $self->{registered_methods} }; }

sub language { my $self = shift; return $self->{language} = shift if @_;

    return $self->{language} unless exists $self->{object};
    return $self->{language} || $self->{class}->i18n->language;
}

# ->inject(attr=>'question',language=>'fr',notes=>$notes, data=>$data); sub inject { my $self = shift; my %opts = @_;

    my $storage_class = $self->{storage_class};
    local($self->{language}) = $opts{language};
    my $storage = $storage_class->new($self->{object}, $opts{attr});
    $storage->store($opts{data});
    return unless $opts{notes} and my $history_class = $self->{history_class};
    $history_class->record($opts{notes});
}

sub is_injected { my $self = shift; my %opts = @_;

    my $storage_class = $self->{storage_class};
    my $storage = $storage_class->new($self->{object}, $opts{attr});
    return $storage->fetch;
}


DESCRIPTION

Object::I18n overrides methods in your class to return international content. It provides one mixin method, i18n(), which returns an Object::I18n object. The object returned is different depending on whether you call it on your class or an instance of your class. See METHODS below.

METHODS

Most methods can be either class methods or object methods but this doesn't mean what you may be accustomed to. A method is considered to act as a class method if it is called on an Object::I18n object returned from the class form of the i18n() method. It acts as an object method when called on the object returned from the object form of the i18n() method.

language [LANGUAGE]
Returns and optionally sets the current language. If called as a class method it affects all instances of a class, except those that have set language() for themselves. If unset, methods should behave as if Object::I18n was not being used at all.

register METHODLIST
Registers the list of method names as i14able. The methods will be overridden so that they return i14ed content when language is set.

storage_class [CLASS]
Returns and optionally set the class that controls how translations are stored.

inject OPTIONS
Injects a new translation into your storage_class. The options are:
language
The language the translation is in. If not set then the language returned by the language() method will be used.

attr
The attribute (method) in your class that the translation is for.

data
The actual translated text to be stored.

notes
Any notes to be saved along with the translation. Requires you to have configured a history_class.


EXPORT

i18n.


AUTHOR

Rick Delaney, <rick@bort.ca>


ACKNOWLEDGEMENTS

To be filled in.


COPYRIGHT AND LICENSE

Copyright (C) 2005 by Rick Delaney

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.3 or, at your option, any later version of Perl 5 you may have available.

 Object::I18n - Internationalize objects