cat.fm

cat.IO.readline<A: Type>(_: A): IO(String)
  use line = IO.ask<String>("get_line", "")
  IO.end<String>(line)

cat.go<A: Type>(io: IO(A)): IO(Unit)
  get bind pure = IO.monad
  let io1 = bind<,>(io, cat.IO.readline<>)
  let io2 = bind<,>(io1, IO.print)

  cat.go<>(io2)

cat: IO(Unit)
  get bind pure = IO.monad
  let io0 = pure<>(Unit.new)
  cat.go<>(io0)