#not idiomatic but shows that the value is encapsulated in a   container that provides extra context used by bind()
    Class Option
      Def __init__(self, x):
          Self.x=x
     Def is_none(self):
          Return self.x is None

    Def bind(val, f):
      If val.is_none():
         # ignore the remainder of the program and return early
         Return None
      Else:
         Return f(val.x)