Methods are associated with types, so it is possible to make any arbitrary Julia object “callable” by adding methods to its type. (Such “callable” objects are sometimes called “functors.”)
In Python, objects that can be called are termed “callables”. In functional programming, “functor” means something, but I’m not seeing if they’re somehow the same concept or just a name coincidence?
Julia uses pretty much the C++ definition of Functor. But functional languages also seem to use a few different meanings for Functor. It’s a vague word.