I think this is a Ruby thing more than a dynamic languages thing. (Not exclusively a Ruby thing mind; Javascript code is also always full of weird edge cases an

I think this is a Ruby thing more than a dynamic languages thing. (Not exclusively a Ruby thing mind; Javascript code is also always full of weird edge cases and gotchas.) I wouldn’t necessarily recommend it, but I have written 500-line Python programs without executing/testing any functions along the way, that “just worked” the first time I ran them with no serious bugs. And not because I am especially clever or have an amazing memory or unusual attention to detail, but just because the code is easy to make clear and straightforward. (But this was just with basic data types and a few standard library modules; dealing with other people’s poorly documented / confusing APIs makes this gets a lot harder.)