let MAKE-NUMBER-INPUT-FIELD accept a default value

scheme/httpd/surflets/surflets.scm

@@ -355,12 +355,15 @@
     (lambda maybe-further-attributes
       (let ((name (generate-input-field-name "number")))
 	(optionals maybe-further-attributes
-	    ((attributes XML-attribute?))
+	    ((default (lambda (a) (or (number? a)
+				      (string-or-symbol? a))))
+	     (attributes XML-attribute?))
 	  (make-input-field 
 	   name
 	   number-input-field-transformer
 	   `(input (@ (type "text")
 		      (name ,name)
+		      (value ,default)
 		      ,(and attributes (cdr attributes))))))))))
 
 (define (make-password-input-field . maybe-further-attributes)

scheme/httpd/surflets/web-server/root/surflets/calculate.scm

@@ -36,7 +36,7 @@
 
     (define (make-number-input-field/default default)
       (if default
-	  (make-number-input-field `(@ (value ,default)))
+	  (make-number-input-field default)
 	  (make-number-input-field)))
     
     (define (show-page operator-pair number1 number2 . maybe-update-text)