Or better yet, do what Python does. Require a constant in front of the 'i', even if it's only '1'. Since identifiers can't begin with a numeral, there's no way

Or better yet, do what Python does. Require a constant in front of the 'i', even if it's only '1'. Since identifiers can't begin with a numeral, there's no way to shadow a valid use of a complex number this way.