ruby find element in array code example

Example 1: ruby find in array

(1..10).detect   { |i| i % 5 == 0 and i % 7 == 0 }   #=> nil
(1..10).find     { |i| i % 5 == 0 and i % 7 == 0 }   #=> nil
(1..100).detect  { |i| i % 5 == 0 and i % 7 == 0 }   #=> 35
(1..100).find    { |i| i % 5 == 0 and i % 7 == 0 }   #=> 35

Example 2: ruby in array

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"]