This extension stores translation stub records for missing translations to the database.

This is useful if you have a web based translation tool. It will populate the database with untranslated keys as the application is being used. A translator can then go through these and add missing translations.

Example usage:

I18n::Backend::Chain.send(:include, I18n::Backend::ActiveRecord::Missing)
I18n.backend = I18nChainBackend.new(I18n::Backend::ActiveRecord.new, I18n::Backend::Simple.new)

Stub records for pluralizations will also be created for each key defined in i18n.plural.keys.

For example:

# en.yml
en:
  i18n:
    plural:
      keys: [:zero, :one, :other]
# pl.yml
pl:
  i18n:
    plural:
      keys: [:zero, :one, :few, :other]

It will also persist interpolation keys in Translation#interpolations so translators will be able to review and use them.

This module allows you to easily cache all responses from the backend - thus speeding up the I18n aspects of your application quite a bit.

To enable caching you can simply include the Cache module to the Simple backend - or whatever other backend you are using:

I18n::Backend::Simple.send(:include, I18n::Backend::Cache)

You will also need to set a cache store implementation that you want to use:

I18n.cache_store = ActiveSupport::Cache.lookup_store(:memory_store)

You can use any cache implementation you want that provides the same API as ActiveSupport::Cache (only the methods fetch and write are being used).

The cache_key implementation assumes that you only pass values to ::translate that return a valid key from hash (see www.ruby-doc.org/core/classes/Object.html#M000337).

EXPERIMENTAL

The Cascade module adds the ability to do cascading lookups to backends that are compatible to the Simple backend.

By cascading lookups we mean that for any key that can not be found the Cascade module strips one segment off the scope part of the key and then tries to look up the key in that scope.

E.g. when a lookup for the key :“foo.bar.baz” does not yield a result then the segment :bar will be stripped off the scope part :“foo.bar” and the new scope :foo will be used to look up the key :baz. If that does not succeed then the remaining scope segment :foo will be omitted, too, and again the key :baz will be looked up (now with no scope).

To enable a cascading lookup one passes the :cascade option:

I18n.t(:'foo.bar.baz', :cascade => true)

This will return the first translation found for :“foo.bar.baz”, :“foo.baz” or :baz in this order.

The cascading lookup takes precedence over resolving any given defaults. I.e. defaults will kick in after the cascading lookups haven't succeeded.

This behavior is useful for libraries like ActiveRecord validations where the library wants to give users a bunch of more or less fine-grained options of scopes for a particular key.

Thanks to Clemens Kofler for the initial idea and implementation! See github.com/clemens/i18n-cascading-backend

I18n locale fallbacks are useful when you want your application to use translations from other locales when translations for the current locale are missing. E.g. you might want to use :en translations when translations in your applications main locale :de are missing.

To enable locale fallbacks you can simply include the Fallbacks module to the Simple backend - or whatever other backend you are using:

I18n::Backend::Simple.send(:include, I18n::Backend::Fallbacks)

Experimental support for using Gettext po files to store translations.

To use this you can simply include the module to the Simple backend - or whatever other backend you are using.

I18n::Backend::Simple.send(:include, I18n::Backend::Gettext)

Now you should be able to include your Gettext translation (*.po) files to the I18n.load_path so they're loaded to the backend and you can use them as usual:

I18n.load_path += Dir["path/to/locales/*.po"]

Following the Gettext convention this implementation expects that your translation files are named by their locales. E.g. the file en.po would contain the translations for the English locale.

The InterpolationCompiler module contains optimizations that can tremendously speed up the interpolation process on the Simple backend.

It works by defining a pre-compiled method on stored translation Strings that already bring all the knowledge about contained interpolation variables etc. so that the actual recurring interpolation will be very fast.

To enable pre-compiled interpolations you can simply include the InterpolationCompiler module to the Simple backend:

I18n::Backend::Simple.send(:include, I18n::Backend::InterpolationCompiler)

Note that InterpolationCompiler does not yield meaningful results and consequently should not be used with Ruby 1.9 (YARV) but improves performance everywhere else (jRuby, Rubinius and 1.8.7).

Memoize module simply memoizes the values returned by lookup using a flat hash and can tremendously speed up the lookup process in a backend.

To enable it you can simply include the Memoize module to your backend:

I18n::Backend::Simple.send(:include, I18n::Backend::Memoize)

Notice that it's the responsibility of the backend to define whenever the cache should be cleaned.

I18n translation metadata is useful when you want to access information about how a translation was looked up, pluralized or interpolated in your application.

msg = I18n.t(:message, :default => 'Hi!', :scope => :foo)
msg.translation_metadata
# => { :key => :message, :scope => :foo, :default => 'Hi!' }

If a :count option was passed to translate it will be set to the metadata. Likewise, if any interpolation variables were passed they will also be set.

To enable translation metadata you can simply include the Metadata module into the Simple backend class - or whatever other backend you are using:

I18n::Backend::Simple.send(:include, I18n::Backend::Metadata)

I18n locale fallbacks are useful when you want your application to use translations from other locales when translations for the current locale are missing. E.g. you might want to use :en translations when translations in your applications main locale :de are missing.

To enable locale specific pluralizations you can simply include the Pluralization module to the Simple backend - or whatever other backend you are using.

I18n::Backend::Simple.send(:include, I18n::Backend::Pluralization)

You also need to make sure to provide pluralization algorithms to the backend, i.e. include them to your I18n.load_path accordingly.

Locale Fallbacks

Extends the I18n module to hold a fallbacks instance which is set to an instance of I18n::Locale::Fallbacks by default but can be swapped with a different implementation.

Locale fallbacks will compute a number of fallback locales for a given locale. For example:

<pre> I18n.fallbacks[:"es-MX"] # => [:"es-MX", :es, :en]</pre>

Locale fallbacks always fall back to

* all parent locales of a given locale (e.g. :es for :"es-MX") first,
* the current default locales and all of their parents second

The default locales are set to [I18n.default_locale] by default but can be set to something else.

One can additionally add any number of additional fallback locales manually. These will be added before the default locales to the fallback chain. For example:

# using the default locale as default fallback locale
I18n.default_locale = :"en-US"
I18n.fallbacks = I18n::Fallbacks.new(:"de-AT" => :"de-DE")
I18n.fallbacks[:"de-AT"] # => [:"de-AT", :"de-DE", :de, :"en-US", :en]
# using a custom locale as default fallback locale
I18n.fallbacks = I18n::Fallbacks.new(:"en-GB", :"de-AT" => :de, :"de-CH" => :de)
I18n.fallbacks[:"de-AT"] # => [:"de-AT", :de, :"en-GB", :en]
I18n.fallbacks[:"de-CH"] # => [:"de-CH", :de, :"en-GB", :en]
# mapping fallbacks to an existing instance
# people speaking Catalan also speak Spanish as spoken in Spain
fallbacks = I18n.fallbacks
fallbacks.map(:ca => :"es-ES")
fallbacks[:ca] # => [:ca, :"es-ES", :es, :"en-US", :en]
# people speaking Arabian as spoken in Palestine also speak Hebrew as spoken in Israel
fallbacks.map(:"ar-PS" => :"he-IL")
fallbacks[:"ar-PS"] # => [:"ar-PS", :ar, :"he-IL", :he, :"en-US", :en]
fallbacks[:"ar-EG"] # => [:"ar-EG", :ar, :"en-US", :en]
# people speaking Sami as spoken in Finnland also speak Swedish and Finnish as spoken in Finnland
fallbacks.map(:sms => [:"se-FI", :"fi-FI"])
fallbacks[:sms] # => [:sms, :"se-FI", :se, :"fi-FI", :fi, :"en-US", :en]

RFC 4646/47 compliant Locale tag implementation that parses locale tags to subtags such as language, script, region, variant etc.

For more information see by en.wikipedia.org/wiki/IETF_language_tag

Rfc4646::Parser does not implement grandfathered tags.

Simple Locale tag implementation that computes subtags by simply splitting the locale tag at '-' occurences.

Namespace
Methods
C
F
L
N
P
R
T
W
Constants
VERSION = "0.4.1"
 
Class Public methods
cache_namespace()
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/cache.rb, line 33
def cache_namespace
  @@cache_namespace
end
cache_namespace=(namespace)
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/cache.rb, line 37
def cache_namespace=(namespace)
  @@cache_namespace = namespace
end
cache_store()
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/cache.rb, line 25
def cache_store
  @@cache_store
end
cache_store=(store)
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/cache.rb, line 29
def cache_store=(store)
  @@cache_store = store
end
config()

Gets I18n configuration object.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 20
def config
  Thread.current[:i18n_config] ||= I18n::Config.new
end
config=(value)

Sets I18n configuration object.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 25
def config=(value)
  Thread.current[:i18n_config] = value
end
fallbacks()

Returns the current fallbacks implementation. Defaults to +I18n::Locale::Fallbacks+.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/fallbacks.rb, line 16
def fallbacks
  @@fallbacks ||= I18n::Locale::Fallbacks.new
end
fallbacks=(fallbacks)

Sets the current fallbacks implementation. Use this to set a different fallbacks implementation.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/fallbacks.rb, line 21
def fallbacks=(fallbacks)
  @@fallbacks = fallbacks
end
l(object, options = {})
localize(object, options = {})

Localizes certain objects, such as dates and numbers to local formatting.

Also aliased as: l
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 227
def localize(object, options = {})
  locale = options.delete(:locale) || config.locale
  format = options.delete(:format) || :default
  config.backend.localize(locale, object, format, options)
end
normalize_keys(locale, key, scope, separator = nil)

Merges the given locale, key and scope into a single array of keys. Splits keys that contain dots into multiple keys. Makes sure all keys are Symbols.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 249
def normalize_keys(locale, key, scope, separator = nil)
  separator ||= I18n.default_separator
  keys = []
  keys.concat normalize_key(locale, separator)
  keys.concat normalize_key(scope, separator)
  keys.concat normalize_key(key, separator)
  keys
end
normalize_translation_keys(*args)
# File activesupport/lib/active_support/vendor.rb, line 32
def self.normalize_translation_keys(*args)
  normalize_keys(*args)
end
perform_caching?()
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n/backend/cache.rb, line 41
def perform_caching?
  !cache_store.nil?
end
reload!()

Tells the backend to reload translations. Used in situations like the Rails development environment. Backends can implement whatever strategy is useful.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 46
def reload!
  config.backend.reload!
end
t(*args)
t!(key, options = {})
translate(*args)

Translates, pluralizes and interpolates a given key using a given locale, scope, and default, as well as interpolation values.

LOOKUP

Translation data is organized as a nested hash using the upper-level keys as namespaces. E.g., ActionView ships with the translation: :date => {:formats => {:short => "%b %d"}}.

Translations can be looked up at any level of this hash using the key argument and the scope option. E.g., in this example I18n.t :date returns the whole translations hash {:formats => {:short => "%b %d"}}.

Key can be either a single key or a dot-separated key (both Strings and Symbols work). E.g., the short format can be looked up using both:

I18n.t 'date.formats.short'
I18n.t :'date.formats.short'

Scope can be either a single key, a dot-separated key or an array of keys or dot-separated keys. Keys and scopes can be combined freely. So these examples will all look up the same short date format:

I18n.t 'date.formats.short'
I18n.t 'formats.short', :scope => 'date'
I18n.t 'short', :scope => 'date.formats'
I18n.t 'short', :scope => %w(date formats)

INTERPOLATION

Translations can contain interpolation variables which will be replaced by values passed to translate as part of the options hash, with the keys matching the interpolation variable names.

E.g., with a translation :foo => "foo %{bar}" the option value for the key barwill be interpolated into the translation:

I18n.t :foo, :bar => 'baz' # => 'foo baz'

PLURALIZATION

Translation data can contain pluralized translations. Pluralized translations are arrays of singluar/plural versions of translations like ['Foo', 'Foos'].

Note that I18n::Backend::Simpleonly supports an algorithm for English pluralization rules. Other algorithms can be supported by custom backends.

This returns the singular version of a pluralized translation:

I18n.t :foo, :count => 1 # => 'Foo'

These both return the plural version of a pluralized translation:

I18n.t :foo, :count => 0 # => 'Foos'
I18n.t :foo, :count => 2 # => 'Foos'

The :countoption can be used both for pluralization and interpolation. E.g., with the translation :foo => ['%{count} foo', '%{count} foos'], count will be interpolated to the pluralized translation:

I18n.t :foo, :count => 1 # => '1 foo'

DEFAULTS

This returns the translation for :fooor default if no translation was found:

I18n.t :foo, :default => 'default'

This returns the translation for :fooor the translation for :barif no translation for :foowas found:

I18n.t :foo, :default => :bar

Returns the translation for :fooor the translation for :baror defaultif no translations for :fooand :barwere found.

I18n.t :foo, :default => [:bar, 'default']

*BULK LOOKUP*

This returns an array with the translations for :fooand :bar.

I18n.t [:foo, :bar]

Can be used with dot-separated nested keys:

I18n.t [:'baz.foo', :'baz.bar']

Which is the same as using a scope option:

I18n.t [:foo, :bar], :scope => :baz

LAMBDAS

Both translations and defaults can be given as Ruby lambdas. Lambdas will be called and passed the key and options.

E.g. assuming the key :salutationresolves to:

lambda { |key, options| options[:gender] == 'm' ? "Mr. %{options[:name]}" : "Mrs. %{options[:name]}" }

Then <tt>::t(:salutation, :gender => 'w', :name => 'Smith') will result in “Mrs. Smith”.

It is recommended to use/implement lambdas in an “idempotent” way. E.g. when a cache layer is put in front of ::translate it will generate a cache key from the argument values passed to translate. Therefor your lambdas should always return the same translations/values per unique combination of argument values.

Also aliased as: t
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 146
def translate(*args)
  options = args.pop if args.last.is_a?(Hash)
  key     = args.shift
  locale  = options && options.delete(:locale) || config.locale
  raises  = options && options.delete(:raise)
  config.backend.translate(locale, key, options || {})
rescue I18n::ArgumentError => exception
  raise exception if raises
  handle_exception(exception, locale, key, options)
end
translate!(key, options = {})
Also aliased as: t!
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 158
def translate!(key, options = {})
  translate(key, options.merge( :raise => true ))
end
transliterate(*args)

Transliterates UTF-8 characters to ASCII. By default this method will transliterate only Latin strings to an ASCII approximation:

I18n.transliterate("Ærøskøbing")
# => "AEroskobing"
I18n.transliterate("日本語")
# => "???"

It's also possible to add support for per-locale transliterations. I18n expects transliteration rules to be stored at i18n.transliterate.rule.

Transliteration rules can either be a Hash or a Proc. Procs must accept a single string argument. Hash rules inherit the default transliteration rules, while Procs do not.

Examples

Setting a Hash in <locale>.yml:

i18n:
  transliterate:
    rule:
      ü: "ue"
      ö: "oe"

Setting a Hash using Ruby:

store_translations(:de, :i18n => {
  :transliterate => {
    :rule => {
      "ü" => "ue",
      "ö" => "oe"
    }
  }
)

Setting a Proc:

translit = lambda {|string| MyTransliterator.transliterate(string) }
store_translations(:xx, :i18n => {:transliterate => {:rule => translit})

Transliterating strings:

I18n.locale = :en
I18n.transliterate("Jürgen") # => "Jurgen"
I18n.locale = :de
I18n.transliterate("Jürgen") # => "Juergen"
I18n.transliterate("Jürgen", :locale => :en) # => "Jurgen"
I18n.transliterate("Jürgen", :locale => :de) # => "Juergen"
# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 214
def transliterate(*args)
  options      = args.pop if args.last.is_a?(Hash)
  key          = args.shift
  locale       = options && options.delete(:locale) || config.locale
  raises       = options && options.delete(:raise)
  replacement  = options && options.delete(:replacement)
  config.backend.transliterate(locale, key, replacement)
rescue I18n::ArgumentError => exception
  raise exception if raises
  handle_exception(exception, locale, key, options)
end
with_locale(tmp_locale = nil)

Executes block with given I18n.locale set.

# File activesupport/lib/active_support/vendor/i18n-0.4.1/i18n.rb, line 235
def with_locale(tmp_locale = nil)
  if tmp_locale
    current_locale = self.locale
    self.locale    = tmp_locale
  end
  yield
ensure
  self.locale = current_locale if tmp_locale
end