That's a NameError in Python: undefined variables don't have a value, not even None. It won't be caught until runtime since there's no AOT compiler in Python, b

That's a NameError in Python: undefined variables don't have a value, not even None. It won't be caught until runtime since there's no AOT compiler in Python, but it's the same kind of error it is in Java. My claim isn't that Python is safer overall than Java. Instead, it's that Java, a language that is mostly type safe, most of the time should not have these two potentially surprising behaviors: 1. The standard string concatenation operator does implicit coercion rather than rejecting an input that isn't a string. There should be a builtin to make a string from any value no matter what for logging and debugging, but that shouldn't be the standard concatenation operator. 2. This is more controversial, but strongly statically typed languages should not allow arbitrary values to be null. That sabotages one of the major strengths of strong static typing. Instead, there should be an option type to make it explicit. For something familiar to most programmers, SQL does this.