úÎønNone+.0BThe 4 function takes a default value, a function, and a  value. If the inner  value is g, the function returns the default value. Otherwise, it applies the function to the value inside the  and returns the result.The & function takes a default value and a  value. If the inner  is R, it returns the default value; otherwise, it returns the value contained within.The   for  is  if either$ of the operands are, whereas here both must be.      both-0.1.0.0 Data.BothBothgetBothbothfromBoth $fMonoidBothbase Data.MaybeMaybeNothingJust Data.Monoidmappend