From 1204af464b8b08d75c26ccfc72fd9fc762e4b01e Mon Sep 17 00:00:00 2001
From: Jason Grout <jgrout6@bloomberg.net>
Date: Fri, 26 Sep 2014 19:04:55 +0000
Subject: [PATCH] on("destroy",...) -> once("destroy",...) so we don't keep a
 reference to it, preventing gc

Thanks to Sylvain Corlay for the suggestion.
---
 IPython/html/static/widgets/js/widget_link.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/IPython/html/static/widgets/js/widget_link.js b/IPython/html/static/widgets/js/widget_link.js
index 7ee00d498..ba76dbd36 100644
--- a/IPython/html/static/widgets/js/widget_link.js
+++ b/IPython/html/static/widgets/js/widget_link.js
@@ -11,7 +11,7 @@ define([
                 this.update_bindings(model.previous("widgets") || [], value);
                 this.update_value(this.get("widgets")[0]);
             }, this);
-            this.on("destroy", function(model, collection, options) {
+            this.once("destroy", function(model, collection, options) {
                 this.update_bindings(this.get("widgets"), []);
             }, this);
         },
@@ -46,7 +46,7 @@ define([
     var DirectionalLinkModel = widget.WidgetModel.extend({
         initialize: function() {
             this.on("change", this.update_bindings, this);
-            this.on("destroy", function() {
+            this.once("destroy", function() {
                 if (this.source) {
                     this.source[0].off("change:" + this.source[1], null, this);
                 }