Flowdock
include?(p1) public

Returns true if the given object is present in self (that is, if any object == anObject), false otherwise.

a = [ "a", "b", "c" ]
a.include?("b")   #=> true
a.include?("z")   #=> false
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May 2, 2009
3 thanks

Test if one array includes the elements of another

You can just use a set difference (aka minus) to see if one array includes all elements of another

not_included = [1,2,3] - (1..9).to_a
not_included      # => []

not_included = [1,2,3,'A'] - (1..9).to_a
not_included      # => ["A"]

Use intersection to test if any of the one are in the other:

shared = [1,2,3,'A'] & (1..9).to_a
shared     # => [1, 2, 3]
February 24, 2009
2 thanks

Test if one array includes the elements of another v2

Maybe a bit more readable way to write the previous snippet would’ve been

puts "yay" if [1, 2, 3].all? { |i| (1..9).include?(i) }
# => "yay"

puts "nope" if [1, 2, 3, 'A'].any? { |i| not (1..9).include?(i) }
# => "nope"
June 22, 2012 - (v1_8_6_287 - v1_9_3_125)
2 thanks

Test if an array is included in another

Array

class Array
   def included_in? array
     array.to_set.superset?(self.to_set)
   end
end

[1,2,4].included_in?([1,10,2,34,4]) #=> true
February 24, 2009
0 thanks

Test if one array includes the elements of another

Recently I’ve written this little snippet:

puts "yay" if [1, 2, 3].each {|i| break unless (1..9).to_a.include?(i)}
# => "yay"

puts "nope" unless [1, 2, 3, 'A'].each {|i| break unless (1..9).to_a.include?(i)}
# => "nope"
November 15, 2013
0 thanks

Test if an array is included in another

a note for anoiaque solution…

before running you need to require set

require 'set'
class Array
  def included_in? array
    array.to_set.superset(self.to_set)
  end
end

[1,2,4].included_in?([1,10,2,34,4]) #=> true