Titleize in ruby

titleize.rb

class String
  def titleize
    u_split = split("_")
    s_split = u_split.map { |s| s.split(" ") }.flatten
    
    if s.split.empty?
      capitalize
    else 
      s_split.map(&:capitalize).join(" ")
    end
  end
end

# "kamesh waran" => "Kamesh Waran"
# "kamesh_waran" => "Kamesh Waran"
# "kamesh_waran s" => "Kamesh Waran S"