Design change: transformer of non-multi input-fields get two

arguments: the input-field *and* the binding value (not only the
binding value)

Rational: (a) transformers of non-multi input-fields can now access the
attribute field of the input-field record, (b) there is no real reason
why to treat multi and non-multi input-fields differently in respect
to their transformer arguments (keep design simple).

Updates of current surflets only necessary if they create their own
non-multi input-fields (with make-input-field).  Example surlfets
calculate.scm and calculate-cb.scm updated as well as standard HTML
input-fields provided by the SUrflets.

scheme/httpd/surflets/input-fields.scm

@@ -124,7 +124,8 @@
       ((real-input-field-transformer real-input-field) input-field bindings))
      ((real-input-field-binding real-input-field bindings) =>
       (lambda (binding)
-	((real-input-field-transformer real-input-field) (cdr binding))))
+	((real-input-field-transformer real-input-field) 
+	 input-field (cdr binding))))
      (else
       (error "no such input-field" input-field bindings)))))
 

scheme/httpd/surflets/surflet-input-fields.scm

@@ -56,10 +56,12 @@
 (define set-simple-field-default! 
   (make-simple-default-setter simple-default?))
 
+(define (second-arg first second) second)
+
 ;;;;;;;;;;;;;;;;;;;;
 ;;; Text input field
 (define make-text-field 
-  (simple-field-maker "text" "text" simple-default? identity))
+  (simple-field-maker "text" "text" simple-default? second-arg))
 (define set-text-field-value! set-simple-field-default!)
 
 ;;;;;;;;;;;;;;;;;;;;;;
@@ -67,7 +69,7 @@
 (define (number-field-default? value)
   (or (number? value)
       (simple-default? value)))
-(define (number-field-transformer string)
+(define (number-field-transformer input-field string)
   (or (string->number string)
       (error "wrong type")))
 (define make-number-field
@@ -82,14 +84,14 @@
 ;; as it is hidden.
 (define make-hidden-field
   (simple-field-maker "hidden" "hidden" 
-		      simple-default? identity))
+		      simple-default? second-arg))
 (define set-hidden-field-value! set-simple-field-default!)
 
 ;;;;;;;;;;;;;;;;;;;;;;;;
 ;;; Password input field
 (define make-password-field 
   (simple-field-maker "password" "password" 
-		      simple-default? identity))
+		      simple-default? second-arg))
 (define set-password-field-value! set-simple-field-default!)
 
 ;;; That's it for simple input fields.
@@ -110,7 +112,7 @@
 			    ,@(sxml-attribute-attributes attributes))))
       (make-input-field 
        name "textarea"
-       identity
+       second-arg
        (make-field-attributes (and default-text)
 			      all-attributes)
        make-textarea-html-tree))))
@@ -282,7 +284,7 @@
 ;; internal
 (define (make-single-select name select-options attributes)
   (make-input-field name "select" 
-		    (lambda (tag)
+		    (lambda (input-field tag)
 		      (cond ((find-select-option-value tag select-options)
 			     => identity)
 			    (else (error "no such option." tag))))
@@ -330,7 +332,7 @@
 	  ((checked? #f boolean?)
 	   (attributes '() sxml-attribute?))
 	(make-input-field name "radio"
-			  identity
+			  second-arg
 			  (make-field-attributes 
 			   (and checked? '(checked))
 			   `((value ,value-string)
@@ -367,7 +369,7 @@
 
 
 (define (make-radio-transformer value-table)
-  (lambda (tag)
+  (lambda (input-field tag)
     (cond 
      ((string->number tag) =>
       (lambda (number)
@@ -420,7 +422,7 @@
 			checkbox-html-tree-maker))))
 
 (define (make-checkbox-transformer value)
-  (lambda (tag)
+  (lambda (input-field tag)
     (if (string=? tag "on")
 	value
 	#f)))
@@ -443,7 +445,7 @@
 ;; button input-fields
 (define (make-button type name button-caption attributes)
   (make-input-field name type
-		    identity
+		    second-arg
 		    (make-field-attributes
 		     (and button-caption `(value ,button-caption))
 		     (sxml-attribute-attributes attributes))

web-server/root/surflets/calculate-cb.scm

@@ -22,7 +22,7 @@
       (let ((name (generate-input-field-name "operator")))
 	(make-input-field 
 	 name
-	 (lambda (operator-string)
+	 (lambda (input-field operator-string)
 	   (cond 
 	    ((assoc operator-string *operator-alist*) =>
 	     (lambda (a) a))

web-server/root/surflets/calculate.scm

@@ -22,7 +22,7 @@
       (let ((name (generate-input-field-name "operator")))
 	(make-input-field 
 	 name "operator"
-	 (lambda (operator-string)
+	 (lambda (input-field operator-string)
 	   (let ((operator (assoc operator-string *operator-alist*)))
 	     (if operator
 		 operator