I really can't believe how stupid people can be to say "const" is a type. Even if Klabnik will say it into my face it will not be true, I don't care about the book he wrote.
You were just told the formatting removed the asterisk. const isn't a type, but a const pointer is, so is a mut pointer. It says so in the book AND it's in the position of a type in the code. What other information do you need to convince you that you're wrong?