A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional inflection rules. Examples: 

  Inflector.inflections 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.

Methods
Included Modules
Attributes
[R] plurals
[R] singulars
[R] uncountables
Public Class methods
new()

[ show source ]

    # File lib/active_support/inflector.rb, line 33
33:       def initialize
34:         @plurals, @singulars, @uncountables = [], [], []
35:       end
Public Instance methods
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.

Examples: 

  clear :all
  clear :plurals

[ show source ]

    # File lib/active_support/inflector.rb, line 84
84:       def clear(scope = :all)
85:         case scope
86:           when :all
87:             @plurals, @singulars, @uncountables = [], [], []
88:           else
89:             instance_variable_set "@#{scope}", []
90:         end
91:       end
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.

Examples: 

  irregular 'octopus', 'octopi'
  irregular 'person', 'people'

[ show source ]

    # File lib/active_support/inflector.rb, line 55
55:       def irregular(singular, plural)
56:         if singular[0,1].upcase == plural[0,1].upcase
57:           plural(Regexp.new("(#{singular[0,1]})#{singular[1..-1]}$", "i"), '\1' + plural[1..-1])
58:           singular(Regexp.new("(#{plural[0,1]})#{plural[1..-1]}$", "i"), '\1' + singular[1..-1])
59:         else
60:           plural(Regexp.new("#{singular[0,1].upcase}(?i)#{singular[1..-1]}$"), plural[0,1].upcase + plural[1..-1])
61:           plural(Regexp.new("#{singular[0,1].downcase}(?i)#{singular[1..-1]}$"), plural[0,1].downcase + plural[1..-1])
62:           singular(Regexp.new("#{plural[0,1].upcase}(?i)#{plural[1..-1]}$"), singular[0,1].upcase + singular[1..-1])
63:           singular(Regexp.new("#{plural[0,1].downcase}(?i)#{plural[1..-1]}$"), singular[0,1].downcase + singular[1..-1])
64:         end
65:       end
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.

[ show source ]

    # File lib/active_support/inflector.rb, line 39
39:       def plural(rule, replacement)
40:         @plurals.insert(0, [rule, replacement])
41:       end
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.

[ show source ]

    # File lib/active_support/inflector.rb, line 45
45:       def singular(rule, replacement)
46:         @singulars.insert(0, [rule, replacement])
47:       end
uncountable(*words)

Add uncountable words that shouldn‘t be attempted inflected.

Examples: 

  uncountable "money"
  uncountable "money", "information"
  uncountable %w( money information rice )

[ show source ]

    # File lib/active_support/inflector.rb, line 73
73:       def uncountable(*words)
74:         (@uncountables << words).flatten!
75:       end