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Action View Translation Helpers

Included Modules


[RW] raise_on_missing_translations

Instance Public methods

l(object, **options)

Alias for: localize

localize(object, **options)

Delegates to I18n.localize with no additional functionality.

See for more information.

Also aliased as: l
# File actionview/lib/action_view/helpers/translation_helper.rb, line 116
def localize(object, **options)
  I18n.localize(object, **options)

t(key, **options)

Alias for: translate

translate(key, **options)

Delegates to I18n#translate but also performs three additional functions.

First, it will ensure that any thrown MissingTranslation messages will be rendered as inline spans that:

  • Have a translation-missing class applied

  • Contain the missing key as the value of the title attribute

  • Have a titleized version of the last key segment as text

For example, the value returned for the missing translation key "" will be:

  title="translation missing:">Title</span>

This allows for views to display rather reasonable strings while still giving developers a way to find missing translations.

If you would prefer missing translations to raise an error, you can opt out of span-wrapping behavior globally by setting config.i18n.raise_on_missing_translations = true or individually by passing raise: true as an option to translate.

Second, if the key starts with a period translate will scope the key by the current partial. Calling translate(".foo") from the people/index.html.erb template is equivalent to calling translate(""). This makes it less repetitive to translate many keys within the same partial and provides a convention to scope keys consistently.

Third, the translation will be marked as html_safe if the key has the suffix “_html” or the last element of the key is “html”. Calling translate("footer_html") or translate("footer.html") will return an HTML safe string that won’t be escaped by other HTML helper methods. This naming convention helps to identify translations that include HTML tags so that you know what kind of output to expect when you call translate in a template and translators know which keys they can provide HTML values for.

To access the translated text along with the fully resolved translation key, translate accepts a block:

<%= translate(".relative_key") do |translation, resolved_key| %>
  <span title="<%= resolved_key %>"><%= translation %></span>
<% end %>

This enables annotate translated text to be aware of the scope it was resolved against.

Also aliased as: t
# File actionview/lib/action_view/helpers/translation_helper.rb, line 73
def translate(key, **options)
  return { |k| translate(k, **options) } if key.is_a?(Array)
  key = key&.to_s unless key.is_a?(Symbol)

  alternatives = if options.key?(:default)
    options[:default].is_a?(Array) ? options.delete(:default).compact : [options.delete(:default)]

  options[:raise] = true if options[:raise].nil? && TranslationHelper.raise_on_missing_translations

  translation = while key || alternatives.present?
    if alternatives.blank? && !options[:raise].nil?
      default = NO_DEFAULT # let I18n handle missing translation

    key = scope_key_by_partial(key)

    translated = ActiveSupport::HtmlSafeTranslation.translate(key, **options, default: default)

    break translated unless translated == MISSING_TRANSLATION

    if alternatives.present? && !alternatives.first.is_a?(Symbol)
      break alternatives.first && I18n.translate(nil, **options, default: alternatives)

    first_key ||= key
    key = alternatives&.shift

  if key.nil? && !first_key.nil?
    translation = missing_translation(first_key, options)
    key = first_key

  block_given? ? yield(translation, key) : translation