Fix some typos

parse.lisp

@@ -163,13 +163,19 @@ non-nil, allow names to be more than one character long."
         finally
            (let ((str (coerce token 'string)))
              (return
-               ;; the multi-char token is an operator. its a variable, so defer
-               ;; to multi-char-names
-               (if (or multi-char-names
+               (string
+                (cond
+                  ;; single character unary operand
+                  ((let ((val (operator-symbol (string (first token)))))
+                     (and (symbolp val) (unary-p val)))
+                   (first token))
+                  ;; multi-char variable, constant (true or false), or operator
+                  ((or multi-char-names
                        (operator-symbol str)
                        (symbolp (interpret-operand str)))
-                   str
-                   (string (first token)))))))
+                   str)
+                  ;; single letter variable (multi-char-names is off)
+                  (t (first token))))))))
 
 (defun next-token (str &key multi-char-names)
   "Return a list of the next token in STR and how much whitespace it had."