### Rails Environment Setup for FastGettext

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Include FastGettext translation capabilities in your Rails application and add text domains. This setup should be done after initializers in config/environment.rb.

```Ruby
# config/environment.rb after initializers
Object.send(:include, FastGettext::Translation)
FastGettext.add_text_domain('accounting', path: 'locale')
FastGettext.add_text_domain('frontend', path: 'locale')
...
```

--------------------------------

### Install FastGettext Gem

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Install the FastGettext gem using the RubyGems package manager.

```Bash
gem install fast_gettext
```

--------------------------------

### Define Custom Translation Repository (WTF)

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Example of defining a custom translation repository by inheriting from TranslationRepository::Base or by defining `available_locales` and `pluralisation_rule`.

```Ruby
# fast_gettext/translation_repository/wtf.rb
module FastGettext
  module TranslationRepository
    class Wtf
      define initialize(name,options), [key], plural(*keys) and
      either inherit from TranslationRepository::Base or define available_locales and pluralisation_rule
    end
  end
end
```

--------------------------------

### Rails Application Controller Setup

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Configure locale settings within your Rails application controller. This includes setting available locales, the default text domain, and the current locale based on request parameters or session.

```Ruby
# app/controllers/application_controller.rb
class ApplicationController ...
  include FastGettext::Translation
  before_filter :set_locale
  def set_locale
    FastGettext.available_locales = ['de', 'en', ...]
    FastGettext.text_domain = 'frontend'
    FastGettext.set_locale(params[:locale] || session[:locale] || request.env['HTTP_ACCEPT_LANGUAGE'])
    session[:locale] = I18n.locale = FastGettext.locale
  end
```

--------------------------------

### Add Text Domain from YAML Files

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Configure FastGettext to use translations from YAML files, following I18n syntax. Locale files should be named with a `qq.yml` suffix.

```Ruby
# A single locale can be segmented in multiple yaml files but they all should be
# named with a `qq.yml` suffix, where `qq` is the locale name.
FastGettext.add_text_domain('my_app', path: 'config/locales', type: :yaml)
```

--------------------------------

### Add Text Domain from PO Files

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Configure FastGettext to use translations from .po files. Options to ignore fuzzy translations and report warnings are available.

```Ruby
FastGettext.add_text_domain('my_app', path: 'locale', type: :po)
# ignore_fuzzy: true to not use fuzzy translations
# report_warning: false to hide warnings about obsolete/fuzzy translations
```

--------------------------------

### Add Text Domain from MO Files

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Configure FastGettext to use translations from .mo files, specifying the text domain and the directory containing the files.

```Ruby
FastGettext.add_text_domain('my_app', path: 'locale')
```

--------------------------------

### Build a Translation Chain

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Create a chain of translation repositories. If a translation is not found in the first repository, FastGettext will query the subsequent ones in the chain.

```Ruby
repos = [
  FastGettext::TranslationRepository.build('new', path: '....'),
  FastGettext::TranslationRepository.build('old', path: '....')
]
FastGettext.add_text_domain 'combined', type: :chain, chain: repos
```

--------------------------------

### Build Merge Repositories

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Construct merge repositories, which are similar to chains but optimize translation lookup by selecting and storing the first available translation upon repository addition.

```Ruby
repos = [
  FastGettext::TranslationRepository.build('new', path: '....'),
  FastGettext::TranslationRepository.build('old', path: '....')
]
domain = FastGettext.add_text_domain 'combined', type: :merge, chain: repos
```

--------------------------------

### Setting the Locale

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

Demonstrates how to set the current locale for translations using either the 'GetText.locale' class method or the 'set_locale' instance method.

```ruby
GetText.locale = "en_US" # translate into english from now on
GetText.locale # => en_US
```

```ruby
include GetText
set_locale "en_US"
```

--------------------------------

### Combined Translation Methods

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

Demonstrates combinations of pluralization and context-aware translation methods for comprehensive localization.

```ruby
np_("Fruit", "Apple", "%{num} Apples", 3)
```

```ruby
ns_("Fruit|Apple","%{num} Apples", 3)
```

```ruby
np_(["Fruit","Apple","%{num} Apples"], 3)
```

```ruby
ns_(["Fruit|Apple","%{num} Apples"], 3)
```

--------------------------------

### Add Text Domain from Database

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Configure FastGettext to use translations stored in a database. This approach is scalable and suitable for many locales and translators. It requires loading default models.

```Ruby
# db access is cached <-> only first lookup hits the db
require "fast_gettext/translation_repository/db"
FastGettext::TranslationRepository::Db.require_models # load and include default models
FastGettext.add_text_domain('my_app', type: :db, model: TranslationKey)
```

--------------------------------

### Set Text Domain and Locale

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Set the current text domain and locale for translations. This should be done once per thread. Available locales can be optionally restricted.

```Ruby
FastGettext.text_domain = 'my_app'
FastGettext.available_locales = ['de', 'en', 'fr', 'en_US', 'en_UK'] # only allow these locales to be set (optional)
FastGettext.locale = 'de'
```

--------------------------------

### Global Multi-Domain Translation Helpers

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Use `TranslationMultidomain` with `D_`, `Dn_`, `Dp_`, `Ds_`, `Dnp_`, and `Dns_` to search for strings across all domains.

```Ruby
extend FastGettext::TranslationMultidomain

D_("string") # finds 'string' in any domain
Dn_("string", "strings", 1) # ditto
Dp_("context", "key")
Ds_("context|key")
Dnp_("context", "string", "strings")
Dns_("context|string", "strings")
```

--------------------------------

### Translation with Context using p_()

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Translate strings with context using the `p_()` or `pgettext()` method. This differentiates translations for the same string used in different contexts.

```Ruby
p_('File', 'Open') == _("File\004Open") == "öffnen"
p_('Context', 'not-found') == 'not-found'
```

--------------------------------

### Binding Text Domains

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

Shows how to bind a specific text domain for translations, allowing for different sets of translations (e.g., financial, human-resource terms).

```ruby
GetText.bindtextdomain('financial')
```

```ruby
include GetText
bindtextdomain('financial')
```

--------------------------------

### Context-Aware Pluralized Translation with pn_()

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Perform pluralized translations that are also context-aware using the `pn_()` or `pngettext()` method.

```Ruby
pn_('Fruit', 'Apple', 'Apples', 3) == 'Äpfel'
pn_('Fruit', 'Apple', 'Apples', 1) == 'Apfel'
```

--------------------------------

### Context-Aware Translation

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

The 'p_()' method provides context-aware translations, useful when a word has multiple meanings. It is equivalent to using 's_()' with a 'context|message' format.

```ruby
p_("Printer","Open") <=> p_("File","Open")
```

```ruby
s_("Printer|Open") <=> s_("File|Open")
```

--------------------------------

### Add Custom Load Path in Rails

Source: https://github.com/grosser/fast_gettext/wiki/Howto:-Extending-FastGettext-with-custom-translation-repository

Add this to your Rails application's config/application.rb to tell Rails where to search for custom libraries.

```ruby
config.autoload_paths += %W(#{config.root}/lib)
```

--------------------------------

### Basic Translation with _()

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Perform basic string translation using the `_()` or `gettext()` method. If a translation is not found, the original message ID is returned.

```Ruby
extend FastGettext::Translation
_('Car') == 'Auto'             # found translation for 'Car'
_('not-found') == 'not-found'  # The msgid is returned by default
```

--------------------------------

### Translation with Namespace using s_()

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Translate strings using a namespace with the `s_()` or `sgettext()` method. This is an alternative to context-based translation, differing mainly in how translations are stored.

```Ruby
s_('File|Open') == _('File|Open') == "öffnen"
s_('Context|not-found') == 'not-found'
```

--------------------------------

### Multi-Domain Translation Helpers

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Use `TranslationMultidomain` to access translation functions for specific domains using `d_`, `dn_`, `dp_`, `ds_`, `dnp_`, and `dns_`.

```Ruby
extend FastGettext::TranslationMultidomain

d_("domainname", "string") # finds 'string' in domain domainname
dn_("domainname", "string", "strings", 1) # ditto
dp_("domainname", "context", "key")
ds_("domainname", "context|key")
dnp_("domainname", "context", "string", "strings")
dns_("domainname", "context|string", "strings")
```

--------------------------------

### Register Custom Translation Repository in Rails Console

Source: https://github.com/grosser/fast_gettext/wiki/Howto:-Extending-FastGettext-with-custom-translation-repository

This snippet shows how to register the custom 'yamlr' translation repository type with FastGettext and add a text domain using it. This is typically done in the Rails console for testing or initialization.

```ruby
require 'fast_gettext/translation_repository/yaml_recursive'
#=> true
FastGettext.add_text_domain('lala', path: 'config/locales', type: :yamlr)
#=> { ...our translations ... }
```

--------------------------------

### Dynamic Translation Availability for Parser

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Use `N_()` and `Nn_()` to make dynamic translations discoverable by the parsing tools. This ensures strings generated at runtime are included in translation files.

```Ruby
N_("active"); N_("inactive"); N_("paused") # possible value of status for parser to find.
Nn_("active", "inactive", "paused")        # alternative method
_("Your account is %{account_state}.") % { account_state: _(status) }
```

--------------------------------

### Logging Missing Translations with Block Default

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Override the `_` method to log missing translation keys when a block default is used and the translation is not found.

```Ruby
# Override _ with logging
def _(key, &block)
  result = gettext(key){ nil } # nil returned when not found
  log_missing_translation_key(key) if result.nil?
  result || (block ? block.call : key)
end
```

--------------------------------

### Custom Yamlr Translation Repository Module

Source: https://github.com/grosser/fast_gettext/wiki/Howto:-Extending-FastGettext-with-custom-translation-repository

This Ruby module extends FastGettext's base translation repository to handle YAML files recursively, supporting multiple files per locale. It merges translations from all YAML files found in the specified path.

```ruby
require 'fast_gettext/translation_repository/base'
require 'yaml'
require 'active_support/core_ext/hash/deep_merge.rb'

module FastGettext
  module TranslationRepository
    # Responsibility:
    #  - find and store yaml files
    #  - provide access to translations in yaml files
    class Yamlr < Base
      def initialize(name,options={})
        super
        reload
      end

      def available_locales
        @files.keys
      end

      def plural(*keys)
        ['one', 'other', 'plural2', 'plural3'].map do |name|
          self[yaml_dot_notation(keys.first, name)]
        end
      end

      def pluralisation_rule
        self['pluralisation_rule'] ? lambda{|n| eval(self['pluralisation_rule']) } : nil
      end

      def reload
        find_and_store_files(@options)
        super
      end

      protected

      MAX_FIND_DEPTH = 10

      def find_and_store_files(options)
        @files = {}
        path = options[:path] || 'config/locales'
        Dir["#{path}/**/*.yml"].each do |yaml_file|
					@files.deep_merge!(load_yaml(yaml_file))
        end
				@files
      end

      def current_translations
        @files[FastGettext.locale] || super
      end

      # Given a yaml file return a hash of key -> translation
      def load_yaml(file)
        yaml = YAML.load_file(file)
				yaml.keys.reduce({}) do |processed, locale|
					processed[locale] ||= {}
					processed[locale].merge!(yaml_hash_to_dot_notation(yaml[locale]))
					processed
				end
      end

      def yaml_hash_to_dot_notation(yaml_hash)
        add_yaml_key({}, nil, yaml_hash)
      end

      def add_yaml_key(result, prefix, hash)
        hash.each_pair do |key, value|
          if value.kind_of?(Hash)
            add_yaml_key(result, yaml_dot_notation(prefix, key), value)
          else
            result[yaml_dot_notation(prefix, key)] = value
          end
        end
        result
      end

      def yaml_dot_notation(a,b)
        a ? "#{a}.#{b}" : b
      end
    end
  end
end

```

--------------------------------

### Basic Translation

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

The basic translation method '_()' translates a given message string.

```ruby
_("Hello")
```

--------------------------------

### Debug Custom Translation Repository Registration

Source: https://github.com/grosser/fast_gettext/wiki/Howto:-Extending-FastGettext-with-custom-translation-repository

Use this code within an initializer or directly in the Rails console to inspect the result of adding a text domain with the custom 'yamlr' translation repository type.

```ruby
puts FastGettext.add_text_domain('lala', path: 'config/locales', type: :yamlr).inspect
```

--------------------------------

### Reload Merge Repository After Locale Change

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

When using merge repositories, you must explicitly reload the domain whenever the locale changes to ensure translations are loaded correctly for the new locale.

```Ruby
FastGettext.locale = 'de'
domain.reload
```

--------------------------------

### Namespace-Aware Pluralized Translation with sn_()

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Perform pluralized translations that are also namespace-aware using the `sn_()` or `sngettext()` method.

```Ruby
sn_('Fruit|Apple', 'Apples', 3) == 'Äpfel'
sn_('Fruit|Apple', 'Apples', 1) == 'Apfel'
```

--------------------------------

### Add Logger to Translation Chain

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Add a logger to a translation repository chain to track untranslated or used keys. The callback can be a lambda or any object responding to `call`.

```Ruby
repos = [
  FastGettext::TranslationRepository.build('app', path: '....')
  FastGettext::TranslationRepository.build('logger', type: :logger, callback: ->(key_or_array_of_ids) { ... }),
}
FastGettext.add_text_domain 'combined', type: :chain, chain: repos
```

--------------------------------

### Parser-Friendly Dynamic Translations

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

The 'N_()' and 'Nn_()' methods are used to make dynamic translation messages readable for the gettext parser, without performing translation at runtime.

```ruby
fruit = N_("Apple")   # same as fruit = "Apple"
_(fruit)              # does a normal translation
```

```ruby
fruits = Nn_("Apple", "%{num} Apples")
n_(fruits, 3)
```

--------------------------------

### Block Default for Untranslated Strings

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

When a translation is not found, a provided block is executed and its return value is used. This is useful for long default passages.

```Ruby
_('not-found'){ "alternative default" } == alternate default
```

--------------------------------

### Custom Pluralization Rule

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Define a custom pluralization rule using a Ruby lambda. This is necessary for languages with pluralization rules that differ from the standard English form.

```Ruby
FastGettext.pluralisation_rule = ->(count){ count > 5 ? 1 : (count > 2 ? 0 : 2)}
```

--------------------------------

### Interpolating Pluralized Translations

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Interpolate values into pluralized translation strings using Ruby's '%' operator. This allows dynamic content within plural forms.

```Ruby
n_('Car', '%{n} Cars', 2) % { n: count } == '2 Autos'
```

--------------------------------

### Translation Without Context Fallback

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

The 's_()' method translates a message and, if no translation is found, returns the original message ID. It can also be used with a context prefix.

```ruby
s_("Printer|Open") # => "Öffnen" #translation found
```

```ruby
s_("Printer|Open") # => "Open"   #translation not found
```

--------------------------------

### Translate within a Specific Locale

Source: https://github.com/grosser/fast_gettext/blob/master/Readme.md

Use the `with_locale` method to perform translations in a locale different from the current one. The original locale is restored afterward.

```Ruby
FastGettext.with_locale 'gsw_CH' do
  FastGettext._('Car was successfully created.')
end
# => "Z auto isch erfolgriich gspeicharat worda."
```

--------------------------------

### Pluralized Translation

Source: https://github.com/grosser/fast_gettext/blob/master/lib/fast_gettext/vendor/README.rdoc

The 'n_()' method handles pluralized translations, returning either the singular or plural form based on the provided count.

```ruby
n_("Apple", "%{num} Apples", 3)
```

```ruby
n_(["Apple", "%{num} Apples"], 3)
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.