Add radix not natural number parser and make backtracking one actuall…

…y backtracking.

greedy.lisp

@@ -112,13 +112,10 @@ non-recursively and has better memory performance."
                                       :tree init-x :suffix inp))))))
       (bind p #'rest-chain))))
 
-(defun nat* ()
+(defun nat* (&optional (radix 10))
   "Non-backtracking parser: accept natural number, consuming as many digits as possible"
-  (chainl1* (named-seq* (<- x (digit?))
-                        (digit-char-p x))
-            (result
-             #'(lambda (x y)
-                 (+ (* 10 x) y)))))
+  (named-seq* (<- number (gather-if* (rcurry #'digit-char-p radix) :result-type 'string))
+   (parse-integer number :radix radix)))
 
 (defun int* ()
   "Non-backtracking parser: accept integer, consuming as many digits as possible"

test-parsers.lisp

@@ -97,6 +97,10 @@
   ("1" 1 "23" 23)
   ("-1"))
 
+(defparsertest test-nat?2 (seq-list? (nat?) "15")
+  ("1015" '(10 "15"))
+  ())
+
 (defparsertest test-chainl1? (chainl1? (digit?) (result #'list))
   ("123" (list (list #\1  #\2) #\3))
   (""))

token-parsers.lisp

@@ -43,8 +43,10 @@
 
 (def-cached-arg-parser nat? (&optional (radix 10))
   "Parser: accept natural numbers"
-  (named-seq* (<- number (gather-if* #'digit-char-p :result-type 'string))
-   (parse-integer number)))
+  (named-seq? (<- number (between? (sat (rcurry #'digit-char-p radix))
+                                   1 nil
+                                   'string))
+   (parse-integer number :radix radix)))
 
 (def-cached-arg-parser int? (&optional (radix 10))
   "Parser: accept an integer, return as integer."