Monad

• Functional XSLT/XPath/XQuery - #5 Monad pattern 15 June 2024

  Functional XSLT/XPath/XQuery - #5 Monad pattern

  The monad is probably the most written about functional pattern, it is famous for convoluted and obtuse explanations, but I will steal some of the better explanations and translate them into XSLT/XPath.

  (adapted directly from All About Monads - HaskellWiki).

  “Suppose that we are writing a program to keep track of sheep cloning experiments. We would certainly want to know the genetic history of all of our sheep, so we would need mother and father functions. But since these are cloned sheep, they may not always have both a mother and a father!