kbp

  x = 2
  x = "foo"
  [y] = [3]
  [y] = ["bar"]

  def main():
      x = 2
      [x] = ["foo"]
      y = 3
      [y] = ["bar"]
      print(x + y)

  main = do
    let x = 2
    let x = "foo"
    y <- pure 3
    y <- pure "bar"
    putStrLn $ x ++ y

  main =
    let x = 2
    in let x = "foo"
       in pure 3 >>= \y ->
                       pure "bar" >>= \y ->
                                        putStrLn $ x ++ y

  irb(main):001:1/ puts(%r
  irb(main):002:1* a+
  irb(main):003:0> .match? %q aaa )
  true

  def
    foo(x)
    bar(x)
  end

  sumTree :: BTree -> Int
  sumTree t = sumTree' [t] 0
    where sumTree' [] total =
            total
          sumTree' (Leaf v : rest) total =
            sumTree' rest (v + total)
          sumTree' (Branch v l r : rest) total =
            sumTree' (l : r : rest) (v + total)