Class: String

Inherits:
Object
  • Object
show all
Defined in:
lib/ruby-extensions/core/string.rb

Overview

Extension to the string class provided by Ruby that provides the following 2 methods:

  • String.pluralize

  • String.singularize

Note that these methods only work for English words, other languages such as Japanese or French aren’t supported at this time (January, 2011). This snippet also doesn’t cover every single english word, patches are welcome!

Author:

  • Yorick Peterse, Michael Fellinger

Since:

  • 1.0

Constant Summary collapse

SingularToPlural =

Constant containing all regular expressions for singular strings (that will be pluralized) and their replacements.

Since:

  • 1.0

{
  /ss$/ => 'sses',
  /se$/ => 'ses',
  /sh$/ => 'shes',
  /ge$/ => 'ges',
  /ch$/ => 'ches',
  /ge$/ => 'ges',
  /g$/  => 'gs',

  # When the singular form ends in a voiceless consonant (other than a sibilant).
  # 
  # lap   => laps
  # cat   => cats
  # clock => clocks
  # cuff  => cuffs
  # death => deaths
  /ap$/ => 'aps',
  /at$/ => 'ats',
  /ck$/ => 'cks',
  /ff$/ => 'ffs',
  /th$/ => 'ths',
  
  # Most nouns ending in o preceded by a consonant also form their plurals by adding -es
  # 
  # hero    => heroes
  # potato  => potatoes
  # volcano => volcanoes or volcanos
  /o$/  => 'oes',
  
  # nouns ending in a y preceded by a consonant usually drop the y and add -ies
  #
  # cherry => cherries
  # lady   => ladies
  # ywzxvtsrqpnmlkjhgfdcb
  # 
  /([bcdfghjklmnpqrstvxzwy]+)y$/ => "\\1ies",
  
  # For all other words (i.e. words ending in vowels or voiced non-sibilants).
  # 
  # boy   => boys
  # girl  => girls
  # chair => chairs
  # quiz  => quizes
  /z$/  => 'zes',
  /y$/  => 'ys',
  /l$/  => 'ls',
  /r$/  => 'rs'
}
PluralToSingular =

Constant containing all regular expressions used to convert plural words to singular words.

Since:

  • 1.0

{
  /sses$/ => 'ss',
  /ses$/  => 'se',
  /shes$/ => 'sh',
  /ges$/  => 'ges',
  /ches$/ => 'ches',
  /ges$/  => 'ges',
  /aps$/  => 'ap',
  /ats$/  => 'at',
  /cks$/  => 'ck',
  /ffs$/  => 'ff',
  /ths$/  => 'th',
  /oes$/  => 'o',
  /ies$/  => 'y',
  /zes$/  => 'z',
  /ys$/   => 'y',
  /l$/    => 'ls',
  /r$/    => 'rs',
  /s$/    => ''
}

Instance Method Summary collapse

Instance Method Details

#pluralize ⇒ String

Tries to convert a string to it’s pluralized version. For example, “user” would result in “users” and “quiz” will result in “quizes”. This method will return the pluralized string, use pluralize! to overwrite the current (singular) version of the string with the pluralized one.

Examples:


"user".pluralize # => users
"baby".pluralize # => babies

Returns:

  • (String) —

    The pluralized version of the string.

Author:

  • Yorick Peterse, Michael Fellinger

Since:

  • 1.0



112
113
114
115
116
117
118
119
120
121
122
123
124
 
# File 'lib/ruby-extensions/core/string.rb', line 112

def pluralize
  string = self.dup
  
  SingularToPlural.each do |regex, replace|
    new_string = string.gsub(regex, replace)
    
    if new_string != string
      return new_string
    end
  end
  
  return string
end

#pluralize! ⇒ Object

Converts the current string into a pluralized form and overwrites the old value rather than returning it.

Examples:


word = "user"
word.pluralize! # => nil

puts word # => users

Since:

  • 1.0



139
140
141
 
# File 'lib/ruby-extensions/core/string.rb', line 139

def pluralize!
  self.replace(self.pluralize)
end

#singularize ⇒ String

Tries to convert the current string into a singular version.

Examples:


"users".singularize  # => user
"babies".singularize # => baby

Returns:

  • (String) —

    a singular form of the string

Author:

  • Yorick Peterse

Since:

  • 1.0



155
156
157
158
159
160
161
162
163
164
165
166
167
 
# File 'lib/ruby-extensions/core/string.rb', line 155

def singularize
  string = self.dup
  
  PluralToSingular.each do |regex, replace|
    new_string = string.gsub(regex, replace)
    
    if new_string != string
      return new_string
    end
  end
  
  return string
end

#singularize! ⇒ Object

Converts a plural string to it’s singular form and replaces the current value of the string with this singular version.

Examples:


word = "users"
word.singularize! # => nil

puts word # => user

Since:

  • 1.0



182
183
184
 
# File 'lib/ruby-extensions/core/string.rb', line 182

def singularize!
  self.replace(self.singularize)
end