gistfile1.rb

george = lambda do
  puts "george"
end

def fred
  puts "fred"
end

def fire
  yield
end

def water obj
  yield(obj)
end

def rach arg
  p "rach: #{arg.inspect}"
end

fire &george
# >> george

fire &method(:fred)
# >> fred

water :fire, &method(:rach)
# >> "rach: :fire"