Some of those in the original presentation can actually happen accidentally because of dynamic typing, though. For example, you could get a value from a JSON object, expect it to be a number, but have objects instead, and perform a {} + {} without actually knowing it, have the interpreter execute it with no error, and wonder where in your code you caught that NaN value (because it would propagate all along).
OTOH, it's very unlikely you type accidentally `true := x` in your code, and even if you did, that would very probably be caught by the compiler anyway.
OTOH, it's very unlikely you type accidentally `true := x` in your code, and even if you did, that would very probably be caught by the compiler anyway.