There is a lot of things we can do with highlighting, but that is not one that we should. An online linting tool should tell you that a variable is shadowing an

There is a lot of things we can do with highlighting, but that is not one that we should. An online linting tool should tell you that a variable is shadowing another (and I personally believe that it should not be possible at all). If you make a syntax highlighter that can color differently based on scope, you're only one stop away from a tool that can warn you about shadowing anyway.