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diff --git a/guides/source/i18n.md b/guides/source/i18n.md index 577efe54a1..ed604c2266 100644 --- a/guides/source/i18n.md +++ b/guides/source/i18n.md @@ -81,26 +81,26 @@ There are just a few simple steps to get up and running with I18n support for yo Following the _convention over configuration_ philosophy, Rails will set up your application with reasonable defaults. If you need different settings, you can overwrite them easily. -Rails adds all +.rb+ and +.yml+ files from the +config/locales+ directory to your *translations load path*, automatically. +Rails adds all `.rb` and `.yml` files from the `config/locales` directory to your *translations load path*, automatically. -The default +en.yml+ locale in this directory contains a sample pair of translation strings: +The default `en.yml` locale in this directory contains a sample pair of translation strings: ```ruby en: hello: "Hello world" ``` -This means, that in the +:en+ locale, the key _hello_ will map to the _Hello world_ string. Every string inside Rails is internationalized in this way, see for instance Active Record validation messages in the "+activerecord/lib/active_record/locale/en.yml+":https://github.com/rails/rails/blob/master/activerecord/lib/active_record/locale/en.yml file or time and date formats in the "+activesupport/lib/active_support/locale/en.yml+":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml file. You can use YAML or standard Ruby Hashes to store translations in the default (Simple) backend. +This means, that in the `:en` locale, the key _hello_ will map to the _Hello world_ string. Every string inside Rails is internationalized in this way, see for instance Active Record validation messages in the "`activerecord/lib/active_record/locale/en.yml`":https://github.com/rails/rails/blob/master/activerecord/lib/active_record/locale/en.yml file or time and date formats in the "`activesupport/lib/active_support/locale/en.yml`":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml file. You can use YAML or standard Ruby Hashes to store translations in the default (Simple) backend. -The I18n library will use *English* as a *default locale*, i.e. if you don't set a different locale, +:en+ will be used for looking up translations. +The I18n library will use *English* as a *default locale*, i.e. if you don't set a different locale, `:en` will be used for looking up translations. -NOTE: The i18n library takes a *pragmatic approach* to locale keys (after "some discussion":http://groups.google.com/group/rails-i18n/browse_thread/thread/14dede2c7dbe9470/80eec34395f64f3c?hl=en), including only the _locale_ ("language") part, like +:en+, +:pl+, not the _region_ part, like +:en-US+ or +:en-GB+, which are traditionally used for separating "languages" and "regional setting" or "dialects". Many international applications use only the "language" element of a locale such as +:cs+, +:th+ or +:es+ (for Czech, Thai and Spanish). However, there are also regional differences within different language groups that may be important. For instance, in the +:en-US+ locale you would have $ as a currency symbol, while in +:en-GB+, you would have £. Nothing stops you from separating regional and other settings in this way: you just have to provide full "English - United Kingdom" locale in a +:en-GB+ dictionary. Various "Rails I18n plugins":http://rails-i18n.org/wiki such as "Globalize2":https://github.com/joshmh/globalize2/tree/master may help you implement it. +NOTE: The i18n library takes a *pragmatic approach* to locale keys (after "some discussion":http://groups.google.com/group/rails-i18n/browse_thread/thread/14dede2c7dbe9470/80eec34395f64f3c?hl=en), including only the _locale_ ("language") part, like `:en`, `:pl`, not the _region_ part, like `:en-US` or `:en-GB`, which are traditionally used for separating "languages" and "regional setting" or "dialects". Many international applications use only the "language" element of a locale such as `:cs`, `:th` or `:es` (for Czech, Thai and Spanish). However, there are also regional differences within different language groups that may be important. For instance, in the `:en-US` locale you would have $ as a currency symbol, while in `:en-GB`, you would have £. Nothing stops you from separating regional and other settings in this way: you just have to provide full "English - United Kingdom" locale in a `:en-GB` dictionary. Various "Rails I18n plugins":http://rails-i18n.org/wiki such as "Globalize2":ht -The *translations load path* (+I18n.load_path+) is just a Ruby Array of paths to your translation files that will be loaded automatically and available in your application. You can pick whatever directory and translation file naming scheme makes sense for you. +The *translations load path* (`I18n.load_path`) is just a Ruby Array of paths to your translation files that will be loaded automatically and available in your application. You can pick whatever directory and translation file naming scheme makes sense for you. NOTE: The backend will lazy-load these translations when a translation is looked up for the first time. This makes it possible to just swap the backend with something else even after translations have already been announced. -The default +application.rb+ files has instructions on how to add locales from another directory and how to set a different default locale. Just uncomment and edit the specific lines. +The default `application.rb` files has instructions on how to add locales from another directory and how to set a different default locale. Just uncomment and edit the specific lines. ```ruby # The default locale is :en and all translations from config/locales/*.rb,yml are auto loaded. @@ -110,7 +110,7 @@ The default +application.rb+ files has instructions on how to add locales from a ### Optional: Custom I18n Configuration Setup -For the sake of completeness, let's mention that if you do not want to use the +application.rb+ file for some reason, you can always wire up things manually, too. +For the sake of completeness, let's mention that if you do not want to use the `application.rb` file for some reason, you can always wire up things manually, too. To tell the I18n library where it can find your custom translation files you can specify the load path anywhere in your application - just make sure it gets run before any translations are actually looked up. You might also want to change the default locale. The simplest thing possible is to put the following into an initializer: @@ -126,13 +126,13 @@ I18n.default_locale = :pt ### Setting and Passing the Locale -If you want to translate your Rails application to a *single language other than English* (the default locale), you can set I18n.default_locale to your locale in +application.rb+ or an initializer as shown above, and it will persist through the requests. +If you want to translate your Rails application to a *single language other than English* (the default locale), you can set I18n.default_locale to your locale in `application.rb` or an initializer as shown above, and it will persist through the requests. However, you would probably like to *provide support for more locales* in your application. In such case, you need to set and pass the locale between requests. WARNING: You may be tempted to store the chosen locale in a _session_ or a <em>cookie</em>, however *do not do this*. The locale should be transparent and a part of the URL. This way you won't break people's basic assumptions about the web itself: if you send a URL to a friend, they should see the same page and content as you. A fancy word for this would be that you're being "<em>RESTful</em>":http://en.wikipedia.org/wiki/Representational_State_Transfer. Read more about the RESTful approach in "Stefan Tilkov's articles":http://www.infoq.com/articles/rest-introduction. Sometimes there are exceptions to this rule and those are discussed below. -The _setting part_ is easy. You can set the locale in a +before_filter+ in the +ApplicationController+ like this: +The _setting part_ is easy. You can set the locale in a `before_filter` in the `ApplicationController` like this: ```ruby before_filter :set_locale @@ -142,20 +142,20 @@ def set_locale end ``` -This requires you to pass the locale as a URL query parameter as in +http://example.com/books?locale=pt+. (This is, for example, Google's approach.) So +http://localhost:3000?locale=pt+ will load the Portuguese localization, whereas +http://localhost:3000?locale=de+ would load the German localization, and so on. You may skip the next section and head over to the *Internationalize your application* section, if you want to try things out by manually placing the locale in the URL and reloading the page. +This requires you to pass the locale as a URL query parameter as in `http://example.com/books?locale=pt`. (This is, for example, Google's approach.) So `http://localhost:3000?locale=pt` will load the Portuguese localization, whereas `http://localhost:3000?locale=de` would load the German localization, and so on. You may skip the next section and head over to the *Internationalize your application* section, if you want to try things out by manually placing the locale in the URL and reloading the page. -Of course, you probably don't want to manually include the locale in every URL all over your application, or want the URLs look differently, e.g. the usual +http://example.com/pt/books+ versus +http://example.com/en/books+. Let's discuss the different options you have. +Of course, you probably don't want to manually include the locale in every URL all over your application, or want the URLs look differently, e.g. the usual `http://example.com/pt/books` versus `http://example.com/en/books`. Let's discuss the different options you have. ### Setting the Locale from the Domain Name -One option you have is to set the locale from the domain name where your application runs. For example, we want +www.example.com+ to load the English (or default) locale, and +www.example.es+ to load the Spanish locale. Thus the _top-level domain name_ is used for locale setting. This has several advantages: +One option you have is to set the locale from the domain name where your application runs. For example, we want `www.example.com` to load the English (or default) locale, and `www.example.es` to load the Spanish locale. Thus the _top-level domain name_ is used for locale setting. This has several advantages: * The locale is an _obvious_ part of the URL. * People intuitively grasp in which language the content will be displayed. * It is very trivial to implement in Rails. * Search engines seem to like that content in different languages lives at different, inter-linked domains. -You can implement it like this in your +ApplicationController+: +You can implement it like this in your `ApplicationController`: ```ruby before_filter :set_locale @@ -195,21 +195,21 @@ If your application includes a locale switching menu, you would then have someth link_to("Deutsch", "#{APP_CONFIG[:deutsch_website_url]}#{request.env['REQUEST_URI']}") ``` -assuming you would set +APP_CONFIG[:deutsch_website_url]+ to some value like +http://www.application.de+. +assuming you would set `APP_CONFIG[:deutsch_website_url]` to some value like `http://www.application.de`. This solution has aforementioned advantages, however, you may not be able or may not want to provide different localizations ("language versions") on different domains. The most obvious solution would be to include locale code in the URL params (or request path). ### Setting the Locale from the URL Params -The most usual way of setting (and passing) the locale would be to include it in URL params, as we did in the +I18n.locale = params[:locale]+ _before_filter_ in the first example. We would like to have URLs like +www.example.com/books?locale=ja+ or +www.example.com/ja/books+ in this case. +The most usual way of setting (and passing) the locale would be to include it in URL params, as we did in the `I18n.locale = params[:locale]` _before_filter_ in the first example. We would like to have URLs like `www.example.com/books?locale=ja` or `www.example.com/ja/books` in this case. This approach has almost the same set of advantages as setting the locale from the domain name: namely that it's RESTful and in accord with the rest of the World Wide Web. It does require a little bit more work to implement, though. -Getting the locale from +params+ and setting it accordingly is not hard; including it in every URL and thus *passing it through the requests* is. To include an explicit option in every URL (e.g. +link_to( books_url(:locale => I18n.locale))+) would be tedious and probably impossible, of course. +Getting the locale from `params` and setting it accordingly is not hard; including it in every URL and thus *passing it through the requests* is. To include an explicit option in every URL (e.g. `link_to( books_url(:locale => I18n.locale))`) would be tedious and probably impossible, of course. -Rails contains infrastructure for "centralizing dynamic decisions about the URLs" in its "+ApplicationController#default_url_options+":http://api.rubyonrails.org/classes/ActionController/Base.html#M000515, which is useful precisely in this scenario: it enables us to set "defaults" for "+url_for+":http://api.rubyonrails.org/classes/ActionController/Base.html#M000503 and helper methods dependent on it (by implementing/overriding this method). +Rails contains infrastructure for "centralizing dynamic decisions about the URLs" in its "`ApplicationController#default_url_options`":http://api.rubyonrails.org/classes/ActionController/Base.html#M000515, which is useful precisely in this scenario: it enables us to set "defaults" for "`url_for`":http://api.rubyonrails.org/classes/ActionController/Base.html#M000503 and helper methods dependent on it (by implementing/overriding this method). -We can include something like this in our +ApplicationController+ then: +We can include something like this in our `ApplicationController` then: ```ruby # app/controllers/application_controller.rb @@ -219,11 +219,11 @@ def default_url_options(options={}) end ``` -Every helper method dependent on +url_for+ (e.g. helpers for named routes like +root_path+ or +root_url+, resource routes like +books_path+ or +books_url+, etc.) will now *automatically include the locale in the query string*, like this: +http://localhost:3001/?locale=ja+. +Every helper method dependent on `url_for` (e.g. helpers for named routes like `root_path` or `root_url`, resource routes like `books_path` or `books_url`, etc.) will now *automatically include the locale in the query string*, like this: `http://localhost:3001/?locale=ja`. You may be satisfied with this. It does impact the readability of URLs, though, when the locale "hangs" at the end of every URL in your application. Moreover, from the architectural standpoint, locale is usually hierarchically above the other parts of the application domain: and URLs should reflect this. -You probably want URLs to look like this: +www.example.com/en/books+ (which loads the English locale) and +www.example.com/nl/books+ (which loads the Dutch locale). This is achievable with the "over-riding +default_url_options+" strategy from above: you just have to set up your routes with "+scoping+":http://api.rubyonrails.org/classes/ActionDispatch/Routing/Mapper/Scoping.html option in this way: +You probably want URLs to look like this: `www.example.com/en/books` (which loads the English locale) and `www.example.com/nl/books` (which loads the Dutch locale). This is achievable with the "over-riding `default_url_options`" strategy from above: you just have to set up your routes with "`scoping`":http://api.rubyonrails.org/classes/ActionDispatch/Routing/Mapper/Scoping.html option in this way: ```ruby # config/routes.rb @@ -232,7 +232,7 @@ scope "/:locale" do end ``` -Now, when you call the +books_path+ method you should get +"/en/books"+ (for the default locale). An URL like +http://localhost:3001/nl/books+ should load the Dutch locale, then, and following calls to +books_path+ should return +"/nl/books"+ (because the locale changed). +Now, when you call the `books_path` method you should get `"/en/books"` (for the default locale). An URL like `http://localhost:3001/nl/books` should load the Dutch locale, then, and following calls to `books_path` should return `"/nl/books"` (because the locale changed). If you don't want to force the use of a locale in your routes you can use an optional path scope (denoted by the parentheses) like so: @@ -243,9 +243,9 @@ scope "(:locale)", :locale => /en|nl/ do end ``` -With this approach you will not get a +Routing Error+ when accessing your resources such as +http://localhost:3001/books+ without a locale. This is useful for when you want to use the default locale when one is not specified. +With this approach you will not get a `Routing Error` when accessing your resources such as `http://localhost:3001/books` without a locale. This is useful for when you want to use the default locale when one is not specified. -Of course, you need to take special care of the root URL (usually "homepage" or "dashboard") of your application. An URL like +http://localhost:3001/nl+ will not work automatically, because the +root :to => "books#index"+ declaration in your +routes.rb+ doesn't take locale into account. (And rightly so: there's only one "root" URL.) +Of course, you need to take special care of the root URL (usually "homepage" or "dashboard") of your application. An URL like `http://localhost:3001/nl` will not work automatically, because the `root :to => "books#index"` declaration in your `routes.rb` doesn't take locale into account. (And rightly so: there's only one "root" URL.) You would probably need to map URLs like these: @@ -254,7 +254,7 @@ You would probably need to map URLs like these: match '/:locale' => 'dashboard#index' ``` -Do take special care about the *order of your routes*, so this route declaration does not "eat" other ones. (You may want to add it directly before the +root :to+ declaration.) +Do take special care about the *order of your routes*, so this route declaration does not "eat" other ones. (You may want to add it directly before the `root :to` declaration.) NOTE: Have a look at two plugins which simplify work with routes in this way: Sven Fuchs's "routing_filter":https://github.com/svenfuchs/routing-filter/tree/master and Raul Murciano's "translate_routes":https://github.com/raul/translate_routes/tree/master. @@ -263,11 +263,11 @@ NOTE: Have a look at two plugins which simplify work with routes in this way: Sv In specific cases, it would make sense to set the locale from client-supplied information, i.e. not from the URL. This information may come for example from the users' preferred language (set in their browser), can be based on the users' geographical location inferred from their IP, or users can provide it simply by choosing the locale in your application interface and saving it to their profile. This approach is more suitable for web-based applications or services, not for websites -- see the box about _sessions_, _cookies_ and RESTful architecture above. -#### Using +Accept-Language+ +#### Using `Accept-Language` -One source of client supplied information would be an +Accept-Language+ HTTP header. People may "set this in their browser":http://www.w3.org/International/questions/qa-lang-priorities or other clients (such as _curl_). +One source of client supplied information would be an `Accept-Language` HTTP header. People may "set this in their browser":http://www.w3.org/International/questions/qa-lang-priorities or other clients (such as _curl_). -A trivial implementation of using an +Accept-Language+ header would be: +A trivial implementation of using an `Accept-Language` header would be: ```ruby def set_locale @@ -322,7 +322,7 @@ end ### Adding Translations -Obviously there are *two strings that are localized to English*. In order to internationalize this code, *replace these strings* with calls to Rails' +#t+ helper with a key that makes sense for the translation: +Obviously there are *two strings that are localized to English*. In order to internationalize this code, *replace these strings* with calls to Rails' `#t` helper with a key that makes sense for the translation: ```ruby # app/controllers/home_controller.rb @@ -337,11 +337,11 @@ end <p><%= flash[:notice] %></p> ``` -When you now render this view, it will show an error message which tells you that the translations for the keys +:hello_world+ and +:hello_flash+ are missing. +When you now render this view, it will show an error message which tells you that the translations for the keys `:hello_world` and `:hello_flash` are missing. !images/i18n/demo_translation_missing.png(rails i18n demo translation missing)! -NOTE: Rails adds a +t+ (+translate+) helper method to your views so that you do not need to spell out +I18n.t+ all the time. Additionally this helper will catch missing translations and wrap the resulting error message into a +<span class="translation_missing">+. +NOTE: Rails adds a `t` (`translate`) helper method to your views so that you do not need to spell out `I18n.t` all the time. Additionally this helper will catch missing translations and wrap the resulting error message into a `<span class="translation_missing">`. So let's add the missing translations into the dictionary files (i.e. do the "localization" part): @@ -361,13 +361,13 @@ There you go. Because you haven't changed the default_locale, I18n will use Engl !images/i18n/demo_translated_en.png(rails i18n demo translated to English)! -And when you change the URL to pass the pirate locale (+http://localhost:3000?locale=pirate+), you'll get: +And when you change the URL to pass the pirate locale (`http://localhost:3000?locale=pirate`), you'll get: !images/i18n/demo_translated_pirate.png(rails i18n demo translated to pirate)! NOTE: You need to restart the server when you add new locale files. -You may use YAML (+.yml+) or plain Ruby (+.rb+) files for storing your translations in SimpleStore. YAML is the preferred option among Rails developers. However, it has one big disadvantage. YAML is very sensitive to whitespace and special characters, so the application may not load your dictionary properly. Ruby files will crash your application on first request, so you may easily find what's wrong. (If you encounter any "weird issues" with YAML dictionaries, try putting the relevant portion of your dictionary into a Ruby file.) +You may use YAML (`.yml`) or plain Ruby (`.rb`) files for storing your translations in SimpleStore. YAML is the preferred option among Rails developers. However, it has one big disadvantage. YAML is very sensitive to whitespace and special characters, so the application may not load your dictionary properly. Ruby files will crash your application on first request, so you may easily find what's wrong. (If you encounter any "weird issues" with YAML dictionaries, try putting the relevant portion of your dictionary into a Ruby file.) ### Passing variables to translations @@ -384,7 +384,7 @@ en: ### Adding Date/Time Formats -OK! Now let's add a timestamp to the view, so we can demo the *date/time localization* feature as well. To localize the time format you pass the Time object to +I18n.l+ or (preferably) use Rails' +#l+ helper. You can pick a format by passing the +:format+ option -- by default the +:default+ format is used. +OK! Now let's add a timestamp to the view, so we can demo the *date/time localization* feature as well. To localize the time format you pass the Time object to `I18n.l` or (preferably) use Rails' `#l` helper. You can pick a format by passing the `:format` option -- by default the `:default` format is used. ```ruby # app/views/home/index.html.erb @@ -407,15 +407,15 @@ So that would give you: !images/i18n/demo_localized_pirate.png(rails i18n demo localized time to pirate)! -TIP: Right now you might need to add some more date/time formats in order to make the I18n backend work as expected (at least for the 'pirate' locale). Of course, there's a great chance that somebody already did all the work by *translating Rails' defaults for your locale*. See the "rails-i18n repository at Github":https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale for an archive of various locale files. When you put such file(s) in +config/locales/+ directory, they will automatically be ready for use. +TIP: Right now you might need to add some more date/time formats in order to make the I18n backend work as expected (at least for the 'pirate' locale). Of course, there's a great chance that somebody already did all the work by *translating Rails' defaults for your locale*. See the "rails-i18n repository at Github":https://github.com/svenfuchs/rails-i18n/tree/master/rails/locale for an archive of various locale files. When you put such file(s) in `config/locales/` directory, they will automatically be ready for use. ### Inflection Rules For Other Locales -Rails 4.0 allows you to define inflection rules (such as rules for singularization and pluralization) for locales other than English. In +config/initializers/inflections.rb+, you can define these rules for multiple locales. The initializer contains a default example for specifying additional rules for English; follow that format for other locales as you see fit. +Rails 4.0 allows you to define inflection rules (such as rules for singularization and pluralization) for locales other than English. In `config/initializers/inflections.rb`, you can define these rules for multiple locales. The initializer contains a default example for specifying additional rules for English; follow that format for other locales as you see fit. ### Localized Views -Rails 2.3 introduces another convenient localization feature: localized views (templates). Let's say you have a _BooksController_ in your application. Your _index_ action renders content in +app/views/books/index.html.erb+ template. When you put a _localized variant_ of this template: *+index.es.html.erb+* in the same directory, Rails will render content in this template, when the locale is set to +:es+. When the locale is set to the default locale, the generic +index.html.erb+ view will be used. (Future Rails versions may well bring this _automagic_ localization to assets in +public+, etc.) +Rails 2.3 introduces another convenient localization feature: localized views (templates). Let's say you have a _BooksController_ in your application. Your _index_ action renders content in `app/views/books/index.html.erb` template. When you put a _localized variant_ of this template: *`index.es.html.erb`* in the same directory, Rails will render content in this template, when the locale is set to `:es`. When the locale is set to the default locale, the generic `index.html.erb` view will be used. (Future Rails versions may well bring this _automagic_ localization to assets in `public`, etc.) You can make use of this feature, e.g. when working with a large amount of static content, which would be clumsy to put inside YAML or Ruby dictionaries. Bear in mind, though, that any change you would like to do later to the template must be propagated to all of them. @@ -423,7 +423,7 @@ You can make use of this feature, e.g. when working with a large amount of stati When you are using the default SimpleStore shipped with the i18n library, dictionaries are stored in plain-text files on the disc. Putting translations for all parts of your application in one file per locale could be hard to manage. You can store these files in a hierarchy which makes sense to you. -For example, your +config/locales+ directory could look like this: +For example, your `config/locales` directory could look like this: ``` |-defaults @@ -484,13 +484,13 @@ I18n.t :message I18n.t 'message' ``` -The +translate+ method also takes a +:scope+ option which can contain one or more additional keys that will be used to specify a “namespace” or scope for a translation key: +The `translate` method also takes a `:scope` option which can contain one or more additional keys that will be used to specify a “namespace” or scope for a translation key: ```ruby I18n.t :record_invalid, :scope => [:activerecord, :errors, :messages] ``` -This looks up the +:record_invalid+ message in the Active Record error messages. +This looks up the `:record_invalid` message in the Active Record error messages. Additionally, both the key and scopes can be specified as dot-separated keys as in: @@ -509,16 +509,16 @@ I18n.t :record_invalid, :scope => [:activerecord, :errors, :messages] #### Defaults -When a +:default+ option is given, its value will be returned if the translation is missing: +When a `:default` option is given, its value will be returned if the translation is missing: ```ruby I18n.t :missing, :default => 'Not here' # => 'Not here' ``` -If the +:default+ value is a Symbol, it will be used as a key and translated. One can provide multiple values as default. The first one that results in a value will be returned. +If the `:default` value is a Symbol, it will be used as a key and translated. One can provide multiple values as default. The first one that results in a value will be returned. -E.g., the following first tries to translate the key +:missing+ and then the key +:also_missing.+ As both do not yield a result, the string "Not here" will be returned: +E.g., the following first tries to translate the key `:missing` and then the key `:also_missing.` As both do not yield a result, the string "Not here" will be returned: ```ruby I18n.t :missing, :default => [:also_missing, 'Not here'] @@ -552,7 +552,7 @@ es: title: "Título" ``` -you can look up the +books.index.title+ value *inside* +app/views/books/index.html.erb+ template like this (note the dot): +you can look up the `books.index.title` value *inside* `app/views/books/index.html.erb` template like this (note the dot): ```ruby <%= t '.title' %> @@ -562,7 +562,7 @@ you can look up the +books.index.title+ value *inside* +app/views/books/index.ht In many cases you want to abstract your translations so that *variables can be interpolated into the translation*. For this reason the I18n API provides an interpolation feature. -All options besides +:default+ and +:scope+ that are passed to +#translate+ will be interpolated to the translation: +All options besides `:default` and `:scope` that are passed to `#translate` will be interpolated to the translation: ```ruby I18n.backend.store_translations :en, :thanks => 'Thanks %{name}!' @@ -570,13 +570,13 @@ I18n.translate :thanks, :name => 'Jeremy' # => 'Thanks Jeremy!' ``` -If a translation uses +:default+ or +:scope+ as an interpolation variable, an +I18n::ReservedInterpolationKey+ exception is raised. If a translation expects an interpolation variable, but this has not been passed to +#translate+, an +I18n::MissingInterpolationArgument+ exception is raised. +If a translation uses `:default` or `:scope` as an interpolation variable, an `I18n::ReservedInterpolationKey` exception is raised. If a translation expects an interpolation variable, but this has not been passed to `#translate`, an `I18n::MissingInterpolationArgument` exception is raised. ### Pluralization In English there are only one singular and one plural form for a given string, e.g. "1 message" and "2 messages". Other languages ("Arabic":http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html#ar, "Japanese":http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html#ja, "Russian":http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html#ru and many more) have different grammars that have additional or fewer "plural forms":http://unicode.org/repos/cldr-tmp/trunk/diff/supplemental/language_plural_rules.html. Thus, the I18n API provides a flexible pluralization feature. -The +:count+ interpolation variable has a special role in that it both is interpolated to the translation and used to pick a pluralization from the translations according to the pluralization rules defined by CLDR: +The `:count` interpolation variable has a special role in that it both is interpolated to the translation and used to pick a pluralization from the translations according to the pluralization rules defined by CLDR: ```ruby I18n.backend.store_translations :en, :inbox => { @@ -590,21 +590,21 @@ I18n.translate :inbox, :count => 1 # => 'one message' ``` -The algorithm for pluralizations in +:en+ is as simple as: +The algorithm for pluralizations in `:en` is as simple as: ```ruby entry[count == 1 ? 0 : 1] ``` -I.e. the translation denoted as +:one+ is regarded as singular, the other is used as plural (including the count being zero). +I.e. the translation denoted as `:one` is regarded as singular, the other is used as plural (including the count being zero). -If the lookup for the key does not return a Hash suitable for pluralization, an +18n::InvalidPluralizationData+ exception is raised. +If the lookup for the key does not return a Hash suitable for pluralization, an `18n::InvalidPluralizationData` exception is raised. ### Setting and Passing a Locale -The locale can be either set pseudo-globally to +I18n.locale+ (which uses +Thread.current+ like, e.g., +Time.zone+) or can be passed as an option to +#translate+ and +#localize+. +The locale can be either set pseudo-globally to `I18n.locale` (which uses `Thread.current` like, e.g., `Time.zone`) or can be passed as an option to `#translate` and `#localize`. -If no locale is passed, +I18n.locale+ is used: +If no locale is passed, `I18n.locale` is used: ```ruby I18n.locale = :de @@ -619,7 +619,7 @@ I18n.t :foo, :locale => :de I18n.l Time.now, :locale => :de ``` -The +I18n.locale+ defaults to +I18n.default_locale+ which defaults to :+en+. The default locale can be set like this: +The `I18n.locale` defaults to `I18n.default_locale` which defaults to :`en`. The default locale can be set like this: ```ruby I18n.default_locale = :de @@ -671,9 +671,9 @@ pt: bar: baz ``` -As you see, in both cases the top level key is the locale. +:foo+ is a namespace key and +:bar+ is the key for the translation "baz". +As you see, in both cases the top level key is the locale. `:foo` is a namespace key and `:bar` is the key for the translation "baz". -Here is a "real" example from the Active Support +en.yml+ translations YAML file: +Here is a "real" example from the Active Support `en.yml` translations YAML file: ```ruby en: @@ -684,7 +684,7 @@ en: long: "%B %d, %Y" ``` -So, all of the following equivalent lookups will return the +:short+ date format +"%B %d"+: +So, all of the following equivalent lookups will return the `:short` date format `"%B %d"`: ```ruby I18n.t 'date.formats.short' @@ -697,7 +697,7 @@ Generally we recommend using YAML as a format for storing translations. There ar ### Translations for Active Record Models -You can use the methods +Model.model_name.human+ and +Model.human_attribute_name(attribute)+ to transparently look up translations for your model and attribute names. +You can use the methods `Model.model_name.human` and `Model.human_attribute_name(attribute)` to transparently look up translations for your model and attribute names. For example when you add the following translations: @@ -712,7 +712,7 @@ en: # will translate User attribute "login" as "Handle" ``` -Then +User.model_name.human+ will return "Dude" and +User.human_attribute_name("login")+ will return "Handle". +Then `User.model_name.human` will return "Dude" and `User.human_attribute_name("login")` will return "Handle". #### Error Message Scopes @@ -728,7 +728,7 @@ class User < ActiveRecord::Base end ``` -The key for the error message in this case is +:blank+. Active Record will look up this key in the namespaces: +The key for the error message in this case is `:blank`. Active Record will look up this key in the namespaces: ```ruby activerecord.errors.models.[model_name].attributes.[attribute_name] @@ -776,9 +776,9 @@ This way you can provide special translations for various error messages at diff The translated model name, translated attribute name, and value are always available for interpolation. -So, for example, instead of the default error message +"can not be blank"+ you could use the attribute name like this : +"Please fill in your %{attribute}"+. +So, for example, instead of the default error message `"can not be blank"` you could use the attribute name like this : `"Please fill in your %{attribute}"`. -* +count+, where available, can be used for pluralization if present: +* `count`, where available, can be used for pluralization if present: |_. validation |_.with option |_.message |_.interpolation| | confirmation | - | :confirmation | -| @@ -803,9 +803,9 @@ So, for example, instead of the default error message +"can not be blank"+ you c | numericality | :odd | :odd | -| | numericality | :even | :even | -| -#### Translations for the Active Record +error_messages_for+ Helper +#### Translations for the Active Record `error_messages_for` Helper -If you are using the Active Record +error_messages_for+ helper, you will want to add translations for it. +If you are using the Active Record `error_messages_for` helper, you will want to add translations for it. Rails ships with the following translations: @@ -826,23 +826,23 @@ Rails uses fixed strings and other localizations, such as format strings and oth #### Action View Helper Methods -* +distance_of_time_in_words+ translates and pluralizes its result and interpolates the number of seconds, minutes, hours, and so on. See "datetime.distance_in_words":https://github.com/rails/rails/blob/master/actionpack/lib/action_view/locale/en.yml#L51 translations. +* `distance_of_time_in_words` translates and pluralizes its result and interpolates the number of seconds, minutes, hours, and so on. See "datetime.distance_in_words":https://github.com/rails/rails/blob/master/actionpack/lib/action_view/locale/en.yml#L51 translations. -* +datetime_select+ and +select_month+ use translated month names for populating the resulting select tag. See "date.month_names":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml#L15 for translations. +datetime_select+ also looks up the order option from "date.order":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml#L18 (unless you pass the option explicitly). All date selection helpers translate the prompt using the translations in the "datetime.prompts":https://github.com/rails/rails/blob/master/actionpack/lib/action_view/locale/en.yml#L83 scope if applicable. +* `datetime_select` and `select_month` use translated month names for populating the resulting select tag. See "date.month_names":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml#L15 for translations. `datetime_select` also looks up the order option from "date.order":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml#L18 (unless you pass the option explicitly). All date selection helpers translate the prompt using the translations in the "datetime.prompts":https://github.com/rails/rails/blob/master/actionpack/lib/action_view/locale/en.yml#L83 scope if applicable. -* The +number_to_currency+, +number_with_precision+, +number_to_percentage+, +number_with_delimiter+, and +number_to_human_size+ helpers use the number format settings located in the "number":https://github.com/rails/rails/blob/master/actionpack/lib/action_view/locale/en.yml#L2 scope. +* The `number_to_currency`, `number_with_precision`, `number_to_percentage`, `number_with_delimiter`, and `number_to_human_size` helpers use the number format settings located in the "number":https://github.com/rails/rails/blob/master/actionpack/lib/action_view/locale/en.yml#L2 scope. #### Active Model Methods -* +model_name.human+ and +human_attribute_name+ use translations for model names and attribute names if available in the "activerecord.models":https://github.com/rails/rails/blob/master/activerecord/lib/active_record/locale/en.yml#L29 scope. They also support translations for inherited class names (e.g. for use with STI) as explained above in "Error message scopes". +* `model_name.human` and `human_attribute_name` use translations for model names and attribute names if available in the "activerecord.models":https://github.com/rails/rails/blob/master/activerecord/lib/active_record/locale/en.yml#L29 scope. They also support translations for inherited class names (e.g. for use with STI) as explained above in "Error message scopes". -* +ActiveModel::Errors#generate_message+ (which is used by Active Model validations but may also be used manually) uses +model_name.human+ and +human_attribute_name+ (see above). It also translates the error message and supports translations for inherited class names as explained above in "Error message scopes". +* `ActiveModel::Errors#generate_message` (which is used by Active Model validations but may also be used manually) uses `model_name.human` and `human_attribute_name` (see above). It also translates the error message and supports translations for inherited class names as explained above in "Error message scopes". -* +ActiveModel::Errors#full_messages+ prepends the attribute name to the error message using a separator that will be looked up from "errors.format":https://github.com/rails/rails/blob/master/activemodel/lib/active_model/locale/en.yml#L4 (and which defaults to +"%{attribute} %{message}"+). +* `ActiveModel::Errors#full_messages` prepends the attribute name to the error message using a separator that will be looked up from "errors.format":https://github.com/rails/rails/blob/master/activemodel/lib/active_model/locale/en.yml#L4 (and which defaults to `"%{attribute} %{message}"`). #### Active Support Methods -* +Array#to_sentence+ uses format settings as given in the "support.array":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml#L30 scope. +* `Array#to_sentence` uses format settings as given in the "support.array":https://github.com/rails/rails/blob/master/activesupport/lib/active_support/locale/en.yml#L30 scope. Customize your I18n Setup ------------------------- @@ -876,11 +876,11 @@ ReservedInterpolationKey # the translation contains a reserved interpolation UnknownFileType # the backend does not know how to handle a file type that was added to I18n.load_path ``` -The I18n API will catch all of these exceptions when they are thrown in the backend and pass them to the default_exception_handler method. This method will re-raise all exceptions except for +MissingTranslationData+ exceptions. When a +MissingTranslationData+ exception has been caught, it will return the exception’s error message string containing the missing key/scope. +The I18n API will catch all of these exceptions when they are thrown in the backend and pass them to the default_exception_handler method. This method will re-raise all exceptions except for `MissingTranslationData` exceptions. When a `MissingTranslationData` exception has been caught, it will return the exception’s error message string containing the missing key/scope. The reason for this is that during development you'd usually want your views to still render even though a translation is missing. -In other contexts you might want to change this behaviour, though. E.g. the default exception handling does not allow to catch missing translations during automated tests easily. For this purpose a different exception handler can be specified. The specified exception handler must be a method on the I18n module or a class with +#call+ method: +In other contexts you might want to change this behaviour, though. E.g. the default exception handling does not allow to catch missing translations during automated tests easily. For this purpose a different exception handler can be specified. The specified exception handler must be a method on the I18n module or a class with `#call` method: ```ruby module I18n @@ -898,9 +898,9 @@ end I18n.exception_handler = I18n::JustRaiseExceptionHandler.new ``` -This would re-raise only the +MissingTranslationData+ exception, passing all other input to the default exception handler. +This would re-raise only the `MissingTranslationData` exception, passing all other input to the default exception handler. -However, if you are using +I18n::Backend::Pluralization+ this handler will also raise +I18n::MissingTranslationData: translation missing: en.i18n.plural.rule+ exception that should normally be ignored to fall back to the default pluralization rule for English locale. To avoid this you may use additional check for translation key: +However, if you are using `I18n::Backend::Pluralization` this handler will also raise `I18n::MissingTranslationData: translation missing: en.i18n.plural.rule` exception that should normally be ignored to fall back to the default pluralization rule for English locale. To avoid this you may use additional check for translation key: ```ruby if exception.is_a?(MissingTranslation) && key.to_s != 'i18n.plural.rule' @@ -910,9 +910,9 @@ else end ``` -Another example where the default behaviour is less desirable is the Rails TranslationHelper which provides the method +#t+ (as well as +#translate+). When a +MissingTranslationData+ exception occurs in this context, the helper wraps the message into a span with the CSS class +translation_missing+. +Another example where the default behaviour is less desirable is the Rails TranslationHelper which provides the method `#t` (as well as `#translate`). When a `MissingTranslationData` exception occurs in this context, the helper wraps the message into a span with the CSS class `translation_missing`. -To do so, the helper forces +I18n#translate+ to raise exceptions no matter what exception handler is defined by setting the +:raise+ option: +To do so, the helper forces `I18n#translate` to raise exceptions no matter what exception handler is defined by setting the `:raise` option: ```ruby I18n.t :foo, :raise => true # always re-raises exceptions from the backend |