I recently came across this expression - but reading up on Wikipedia did not clarify it much for me - I still don\'t get it:
Nothing wrong with a bit of (very simple) JavaScript to describe new and important concepts. Perfectly doable in C++, too.cept
Key concept: using Functional Programming idiom, describe the interface. Without using: message argument as a string, to be parsed, concept.
I think it is mostly related to the "Facade" pattern, but yes, it is related to a "Builder pattern". And it seems it survived the "Monads" too.
btw: All the advocates above have presented very good use-cases.