Creating reusable functions and types and whatnot is also creating your own DSL, as another poster hinted at. However the main problem with bad DSLs is that th

Creating reusable functions and types and whatnot is also creating your own DSL, as another poster hinted at. However the main problem with bad DSLs is that they aren't composable. Which really means users have to learn the right sequence of events and the right context in which certain actions function properly. People often complain about awkward symbols or unfamiliar constructs, but really, they are missing the forest from the trees. This is why plain pure functions are always better, because they are composable and reusable, being the missing ingredient of many DSL authors.