Make whitespace? and word? backtracking, export new symbols.

greedy.lisp

@@ -112,6 +112,16 @@ non-recursively and has better memory performance."
                                       :tree init-x :suffix inp))))))
       (bind p #'rest-chain))))
 
+(def-cached-arg-parser whitespace* (&key (result-type nil) (accept-empty nil))
+  "Non-backtracking parser: accept a sequence of whitespace characters."
+  (gather-if* (rcurry #'member '(#\Space #\Newline #\	))
+              :result-type result-type
+              :accept-empty accept-empty))
+
+(def-cached-parser word*
+  "Parser: accept a string of alphabetic characters"
+  (gather-if* #'alpha-char-p :result-type 'string))
+
 (defun nat* (&optional (radix 10))
   "Non-backtracking parser: accept natural number, consuming as many digits as possible"
   (named-seq* (<- number (gather-if* (rcurry #'digit-char-p radix) :result-type 'string))

package.lisp

@@ -18,6 +18,9 @@
            #:letter?
            #:alphanum?
            #:word?
+           #:word*
+           #:whitespace?
+           #:whitespace*
            #:string?
            #:many?
            #:many1?

token-parsers.lisp

@@ -26,13 +26,14 @@
 
 (def-cached-arg-parser whitespace? (&key (result-type nil) (accept-empty nil))
   "Parser: accept a sequence of whitespace characters."
-  (gather-if* (rcurry #'member '(#\Space #\Newline #\	))
-              :result-type result-type
-              :accept-empty accept-empty))
+  (between? (sat (rcurry #'member '(#\Space #\Newline #\	)))
+            (if accept-empty nil 1)
+            nil
+             result-type))
 
 (def-cached-parser word?
   "Parser: accept a string of alphabetic characters"
-  (gather-if* #'alpha-char-p :result-type 'string))
+  (between? (alphanum?) 1 nil 'string))
 
 ;; naive implementation using monadic combinators, unfortunately rather slow
 ;; (defun int? ()