Great question! Unary operators are really simple to add: you just look for the operator symbol first thing at the right level of precedence. Same idea as "if (

Great question! Unary operators are really simple to add: you just look for the operator symbol first thing at the right level of precedence. Same idea as "if (peek == '(') ..." for parentheses, but outside the code that deals with '*' and '^' (if you want those to bind more strongly).