1 files changed, 8 insertions, 0 deletions
diff --git a/lib/js/urweb.js b/lib/js/urweb.js
index ebe192ca..1a275451 100644
--- a/lib/js/urweb.js
+++ b/lib/js/urweb.js
@@ -1389,6 +1389,14 @@ function addOnChange(x, f) {
         x.onchange = function() { old(); f(); };
 }
 
+function addOnInput(x, f) {
+    var old = x.oninput;
+    if (old == null)
+        x.oninput = f;
+    else
+        x.oninput = function() { old(); f(); };
+}
+
 function addOnKeyUp(x, f) {
     var old = x.onkeyup;
     if (old == null)