[weberc2]

This tends to be more important in dynamic languages where "the outputs" are often hilariously far from what is reasonable to expect. At least that's where I find I use a REPL in Python--load in some poorly-documented 3rd party library to see what the return type of a function is (for some given inputs) and what properties are available on that object (since the "type" isn't much good given the aforementioned poor state of the docs). In Go, however, you get all the information you need from the type and godoc.org.

[stcredzero]

This tends to be more important in dynamic languages where "the outputs" are often hilariously far from what is reasonable to expect.

Most of my experience with dynamic language programming is far from what you describe above. About the only place where I've encountered the like is with Javascript.

https://archive.org/details/wat_destroyallsoftware

I once experienced "magic" jumps in the debugger in Smalltalk, but that was because of some liberties taken with custom methods implemented in C, or because of missing_method style metaprogramming. (#doesNotUndedrstand: in Smalltalk)

[weberc2]

This experience is commonplace in Python. Can’t speak so much for other languages.