Haskell GHC 9.0.1-alpha(mail.haskell.org)

  main = do x <- getLine
            putStrLn ("Hello, " ++ x)  

  (>>=) :: m a -> (a -> m b) -> m b
  pure  :: a -> m a

    foo.append(bar.append(baz))
    foo.append(bar).append(baz)

      mean(mean(1, 3), 4)
    = mean(2         , 4)
    = 3

      mean(1, mean(3, 4))
    = mean(1, 3.5)
    = 2.25

      mean(mean(1/1, 3/1), 4/1)
    = mean(4/2           , 4/1)
    = 8/3

      mean(1/1, mean(3/1, 4/1))
    = mean(1/1, 7/2)
    = 8/3

    const append = function append(f, g) {
      return "lambda x: (" + f + ")((" + g + ")(x))";
    }

    console.log(append("lambda x: x+1", "lambda x: 2*x"));

    > "lambda x: (lambda x: x+1)((lambda x: 2*x)(x))"

    impl A { 
      fn use(&mut self) { 
        // takes a mutable reference to self, so it
        // can be used again later
      }

      fn consume(self) {
        // moves self into this function, which means
        // it cannot be used again
      }
    }