Comment by greggman3

Undefined variables is already a thing in most IDEs? I know VSCode does it. I can't imagine the others don't.

One interesting thing I've found in JavaScript (and I'm guessing it would be useful in Python) is the CodeSpell plugin for VSCode

https://marketplace.visualstudio.com/items?itemName=streetsi...

It spell checks code by separating camelCaseWords and identifiers_with_underscores. Sure it's not "smart" but for dynamic languages, at least for me, it helps prevent bugs. A static language the IDE would already have the info it needs to highlight a non-existent property but in a dynamic language generally not so I've found it quite useful.