case MUL, QUO, REM, SHL, SHR, AND, AND_NOT:
		return 5
	}
	return LowestPrec
}

var keywords map[string]Token

func init() {
	keywords = make(map[string]Token, keyword_end-(keyword_beg+1))
	for i := keyword_beg + 1; i < keyword_end; i++ {
		keywords[tokens[i]] = i
	}
}

// Lookup maps an identifier to its keyword token or [IDENT] (if not a keyword).
func Lookup(ident string) Token {