A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional inflection rules. If passed an optional locale, rules for other languages can be specified. The default locale is :en. Only rules for English are provided.

ActiveSupport::Inflector.inflections(:en) do |inflect|
  inflect.plural /^(ox)$/i, '\1\2en'
  inflect.singular /^(ox)en/i, '\1'

  inflect.irregular 'octopus', 'octopi'

  inflect.uncountable 'equipment'
end

New rules are added at the top. So in the example above, the irregular rule for octopus will now be the first of the pluralization and singularization rules that is runs. This guarantees that your rules run before any of the rules that may already have been loaded.

Namespace

Class

Methods

Attributes

[R] acronyms
[R] humans
[R] plurals
[R] singulars
[R] uncountables

Class Public methods

instance(locale = :en)

📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 63
      def self.instance(locale = :en)
        @__instance__[locale] ||= new
      end
🔎 See on GitHub

new()

📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 71
      def initialize
        @plurals, @singulars, @uncountables, @humans, @acronyms = [], [], Uncountables.new, [], {}
        define_acronym_regex_patterns
      end
🔎 See on GitHub

Instance Public methods

acronym(word)

Specifies a new acronym. An acronym must be specified as it will appear in a camelized string. An underscore string that contains the acronym will retain the acronym when passed to camelize, humanize, or titleize. A camelized string that contains the acronym will maintain the acronym when titleized or humanized, and will convert the acronym into a non-delimited single lowercase word when passed to underscore.

acronym 'HTML'
titleize 'html'     # => 'HTML'
camelize 'html'     # => 'HTML'
underscore 'MyHTML' # => 'my_html'

The acronym, however, must occur as a delimited unit and not be part of another word for conversions to recognize it:

acronym 'HTTP'
camelize 'my_http_delimited' # => 'MyHTTPDelimited'
camelize 'https'             # => 'Https', not 'HTTPs'
underscore 'HTTPS'           # => 'http_s', not 'https'

acronym 'HTTPS'
camelize 'https'   # => 'HTTPS'
underscore 'HTTPS' # => 'https'

Note: Acronyms that are passed to pluralize will no longer be recognized, since the acronym will not occur as a delimited unit in the pluralized result. To work around this, you must specify the pluralized form as an acronym as well:

acronym 'API'
camelize(pluralize('api')) # => 'Apis'

acronym 'APIs'
camelize(pluralize('api')) # => 'APIs'

acronym may be used to specify any word that contains an acronym or otherwise needs to maintain a non-standard capitalization. The only restriction is that the word must begin with a capital letter.

acronym 'RESTful'
underscore 'RESTful'           # => 'restful'
underscore 'RESTfulController' # => 'restful_controller'
titleize 'RESTfulController'   # => 'RESTful Controller'
camelize 'restful'             # => 'RESTful'
camelize 'restful_controller'  # => 'RESTfulController'

acronym 'McDonald'
underscore 'McDonald' # => 'mcdonald'
camelize 'mcdonald'   # => 'McDonald'
📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 133
      def acronym(word)
        @acronyms[word.downcase] = word
        define_acronym_regex_patterns
      end
🔎 See on GitHub

clear(scope = :all)

Clears the loaded inflections within a given scope (default is :all). Give the scope as a symbol of the inflection type, the options are: :plurals, :singulars, :uncountables, :humans.

clear :all
clear :plurals
📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 222
      def clear(scope = :all)
        case scope
        when :all
          @plurals, @singulars, @uncountables, @humans = [], [], Uncountables.new, []
        else
          instance_variable_set "@#{scope}", []
        end
      end
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human(rule, replacement)

Specifies a humanized form of a string by a regular expression rule or by a string mapping. When using a regular expression based replacement, the normal humanize formatting is called after the replacement. When a string is used, the human form should be specified as desired (example: 'The name', not 'the_name').

human /_cnt$/i, '\1_count'
human 'legacy_col_person_name', 'Name'
📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 211
      def human(rule, replacement)
        @humans.prepend([rule, replacement])
      end
🔎 See on GitHub

irregular(singular, plural)

Specifies a new irregular that applies to both pluralization and singularization at the same time. This can only be used for strings, not regular expressions. You simply pass the irregular in singular and plural form.

irregular 'octopus', 'octopi'
irregular 'person', 'people'
📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 165
      def irregular(singular, plural)
        @uncountables.delete(singular)
        @uncountables.delete(plural)

        s0 = singular[0]
        srest = singular[1..-1]

        p0 = plural[0]
        prest = plural[1..-1]

        if s0.upcase == p0.upcase
          plural(/(#{s0})#{srest}$/i, '\1' + prest)
          plural(/(#{p0})#{prest}$/i, '\1' + prest)

          singular(/(#{s0})#{srest}$/i, '\1' + srest)
          singular(/(#{p0})#{prest}$/i, '\1' + srest)
        else
          plural(/#{s0.upcase}(?i)#{srest}$/,   p0.upcase   + prest)
          plural(/#{s0.downcase}(?i)#{srest}$/, p0.downcase + prest)
          plural(/#{p0.upcase}(?i)#{prest}$/,   p0.upcase   + prest)
          plural(/#{p0.downcase}(?i)#{prest}$/, p0.downcase + prest)

          singular(/#{s0.upcase}(?i)#{srest}$/,   s0.upcase   + srest)
          singular(/#{s0.downcase}(?i)#{srest}$/, s0.downcase + srest)
          singular(/#{p0.upcase}(?i)#{prest}$/,   s0.upcase   + srest)
          singular(/#{p0.downcase}(?i)#{prest}$/, s0.downcase + srest)
        end
      end
🔎 See on GitHub

plural(rule, replacement)

Specifies a new pluralization rule and its replacement. The rule can either be a string or a regular expression. The replacement should always be a string that may include references to the matched data from the rule.

📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 142
      def plural(rule, replacement)
        @uncountables.delete(rule) if rule.is_a?(String)
        @uncountables.delete(replacement)
        @plurals.prepend([rule, replacement])
      end
🔎 See on GitHub

singular(rule, replacement)

Specifies a new singularization rule and its replacement. The rule can either be a string or a regular expression. The replacement should always be a string that may include references to the matched data from the rule.

📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 152
      def singular(rule, replacement)
        @uncountables.delete(rule) if rule.is_a?(String)
        @uncountables.delete(replacement)
        @singulars.prepend([rule, replacement])
      end
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uncountable(*words)

Specifies words that are uncountable and should not be inflected.

uncountable 'money'
uncountable 'money', 'information'
uncountable %w( money information rice )
📝 Source code 
# File activesupport/lib/active_support/inflector/inflections.rb, line 199
      def uncountable(*words)
        @uncountables.add(words)
      end
🔎 See on GitHub