factor out generating of 'unique' numbers

scheme/httpd/surflets/packages.scm

@@ -307,6 +307,7 @@
 (define-interface surflets/utilities-interface
   (export form-query-list
 	  rev-append
+	  generate-unique-number
 	  generate-unique-name))
 
 ;; Intelligent Addresses

scheme/httpd/surflets/utilities.scm

@@ -20,9 +20,14 @@
 	(rev-app (cdr a) (cons (car a) b))
 	b)))
 
-;; FIXME: consider creating small names
-(define generate-unique-name
+;; Every call will surely return another number.
+(define generate-unique-number
   (let ((id 0))
-    (lambda (type-string)
+    (lambda ()
       (set! id (+ 1 id))
-      (string-append type-string (number->string id)))))
+      id)))
+
+;; FIXME: consider creating small names
+(define (generate-unique-name type-string)
+  (string-append type-string 
+		 (number->string (generate-unique-number))))