find_value.rb

module Enumerable
  def find_value(&block)
    found = nil
    self.each do |e|
      found = block.call(e)
      return found if found
    end
    found
  end
end

def profession(man)
  { 'einstein' => 'scientist', 'edison' => 'inventor', 'nietzsche' => 'philosopher' }[man]
end

def find_famous_profession(famous_people)
  famous_people.find_value { |famous| profession(famous) }
end

p find_famous_profession(['hume', 'turing', 'yeats', 'nietzsche'])