How to split a string into only two parts, by the last occurrence of the split char?

Question

For example:

\"Angry Birds 2.4.1\".split(\" \", 2)
 => [\"Angry\", \"Birds 2.4.1\"] 

How can I split the string into: [\"Angry Bir

Answer 1

Create a String#split_on_last method.

Heavily inspired by halfelf's answer but permits more than just a single character, doesn't have a default param value and refactored for clarity.

Definition

Class String
  def split_on_last( text )
    position_of_last_occurrence = self.rindex( text )

    return self if position_of_last_occurrence.nil?

    first_part = self[ 0...position_of_last_occurrence ]
    last_part  = self[ position_of_last_occurrence + text.length..-1 ]

    [ first_part, last_part ]
  end
end

Usage

"Angry Birds 2.4.1".split_on_last( " " )
#=> ["Angry Birds", "2.4.1"]

"start middle end end suffix".split_on_last( "end" )
=> ["start middle end ", " suffix"]