--- a/lib/js/urweb.js	Thu May 21 10:18:20 2009 -0400
+++ b/lib/js/urweb.js	Thu May 21 10:34:56 2009 -0400
@@ -295,12 +295,12 @@
   populate(x);
 }
 
-function input(t, s) {
+function input(t, s, recreate) {
   var x = document.createElement(t);
   x.dead = false;
   x.signal = ss(s);
   x.sources = null;
-  x.recreate = function(v) { if (x.value != v) x.value = v; };
+  x.recreate = recreate(x);
   populate(x);
   addNode(x);
 
@@ -308,7 +308,7 @@
 }
 
 function inp(s) {
-  var x = input("input", s);
+  var x = input("input", s, function(x) { return function(v) { if (x.value != v) x.value = v; }; });
   x.value = s.data;
   x.onkeyup = function() { sv(s, x.value) };
 
@@ -316,7 +316,7 @@
 }
 
 function sel(s, content) {
-  var x = input("select", s);
+  var x = input("select", s, function(x) { return function(v) { if (x.value != v) x.value = v; }; });
   x.innerHTML = content;
   x.value = s.data;
   x.onchange = function() { sv(s, x.value) };
@@ -324,6 +324,15 @@
   return x;
 }
 
+function chk(s) {
+  var x = input("input", s, function(x) { return function(v) { if (x.checked != v) x.checked = v; }; });
+  x.type = "checkbox";
+  x.checked = s.data;
+  x.onchange = function() { sv(s, x.checked) };
+
+  return x;
+}
+
 function addOnChange(x, f) {
   var old = x.onchange;
   x.onchange = function() { old(); f (); };

--- a/lib/ur/basis.urs	Thu May 21 10:18:20 2009 -0400
+++ b/lib/ur/basis.urs	Thu May 21 10:34:56 2009 -0400
@@ -631,6 +631,8 @@
 val ctextbox : cformTag [Value = string, Size = int, Source = source string] []
 val button : cformTag [Value = string, Onclick = transaction unit] []
 
+val ccheckbox : cformTag [Value = bool, Size = int, Source = source bool] []
+
 con cselect = [Cselect]
 val cselect : cformTag [Source = source string,
                         Onchange = transaction unit] cselect

--- a/src/monoize.sml	Thu May 21 10:18:20 2009 -0400
+++ b/src/monoize.sml	Thu May 21 10:34:56 2009 -0400
@@ -2648,6 +2648,29 @@
                               fm)
                          end)
 
+                  | "ccheckbox" =>
+                    (case List.find (fn ("Source", _, _) => true | _ => false) attrs of
+                         NONE =>
+                         let
+                             val (ts, fm) = tagStart "input type=\"checkbox\""
+                         in
+                             ((L'.EStrcat (ts,
+                                           (L'.EPrim (Prim.String " />"), loc)),
+                               loc), fm)
+                         end
+                       | SOME (_, src, _) =>
+                         let
+                             val sc = strcat [str "chk(",
+                                              (L'.EJavaScript (L'.Script, src), loc),
+                                              str ")"]
+                             val sc = setAttrs sc
+                         in
+                             (strcat [str "<span><script type=\"text/javascript\">",
+                                      sc,
+                                      str "</script></span>"],
+                              fm)
+                         end)
+
                   | "cselect" =>
                     (case List.find (fn ("Source", _, _) => true | _ => false) attrs of
                          NONE =>