method

to_sentence

v3.2.13 - Show latest stable - Class: Array

to_sentence(options = {})

public

Converts the array to a comma-separated sentence where the last element is joined by the connector word. Options:

:words_connector - The sign or word used to join the elements in arrays with two or more elements (default: “, ”)
:two_words_connector - The sign or word used to join the elements in arrays with two elements (default: “ and ”)
:last_word_connector - The sign or word used to join the last element in arrays with three or more elements (default: “, and ”)

# File activesupport/lib/active_support/core_ext/array/conversions.rb, line 11
  def to_sentence(options = {})
    if defined?(I18n)
      default_words_connector     = I18n.translate(:'support.array.words_connector',     :locale => options[:locale])
      default_two_words_connector = I18n.translate(:'support.array.two_words_connector', :locale => options[:locale])
      default_last_word_connector = I18n.translate(:'support.array.last_word_connector', :locale => options[:locale])
    else
      default_words_connector     = ", "
      default_two_words_connector = " and "
      default_last_word_connector = ", and "
    end

    options.assert_valid_keys(:words_connector, :two_words_connector, :last_word_connector, :locale)
    options.reverse_merge! :words_connector => default_words_connector, :two_words_connector => default_two_words_connector, :last_word_connector => default_last_word_connector

    case length
      when 0
        ""
      when 1
        self[0].to_s.dup
      when 2
        "#{self[0]}#{options[:two_words_connector]}#{self[1]}"
      else
        "#{self[0...-1].join(options[:words_connector])}#{options[:last_word_connector]}#{self[-1]}"
    end
  end

5Notes

example

francois · Dec 17, 20112 thanks

['one','two','three'].to_sentence

=> "one, two, and three"

Sometimes, you need the "Oxford comma"

rab · Apr 1, 20142 thanks

Re: Gramatical error

http://imgur.com/fycHx

=== We invited the strippers, JFK, and Stalin.

versus the appositive phrase:

=== We invited the strippers, JFK and Stalin.

(Really, you need to see the comic to appreciate the difference.)

Grammatical error

rajivekjain · Apr 1, 2014

Hi - not sure where I would submit this so just putting here. My apologies if not in the right place.

default: “, and ” - this is grammatically wrong. There should be no comma with the last and.

Example:

['one', 'two', 'three'].to_sentence

should give: "one, two and three"

There is no ' .... , and ' which is considered grammatically incorrect I feel. The 'and' does it's job in the English language quite well by joining the two words it's in between.

Thank you.

No grammatical error

marnen · Mar 17, 2016

rajivekjain:

"A, B, and C" is correct in English, and is preferred by most style manuals. "A, B and C" is also correct in English. See https://en.wikipedia.org/wiki/Serial_comma

to_sentence_exclusive

joshuapinter · May 28, 2019

By default, +to_sentence+ combines elements inclusively by using ", and ".

If you want to be exclusive and combine the elements using ", or ", you can either pass in lengthy options to +to_sentence+ or use this handy extension I made to add +to_sentence_exclusive+ to the +Array+ class.

class Array

# Adds a simple method that overloads `to_sentence` except it uses "or" instead of "and", which is the default.
# The reason for this is because `to_sentence` is extremely flexible but that results in a lot of code to get
# the simple result of using "or" instead of "and". This makes it simple.
#
def to_sentence_exclusive
  self.to_sentence( two_words_connector: " or ", last_word_connector: ", or " )
end

end

Just drop this in +config/initializers/to_sentence_exclusive.rb+, restart your server or console and Bob's your uncle.