Add support for th-navigating event

core/modules/widgets/navigator.js

@@ -174,6 +174,7 @@ NavigatorWidget.prototype.addToHistory = function(title,fromPageRect) {
 Handle a tm-navigate event
 */
 NavigatorWidget.prototype.handleNavigateEvent = function(event) {
+	event = $tw.hooks.invokeHook("th-navigating",event);
 	if(event.navigateTo) {
 		this.addToStory(event.navigateTo,event.navigateFromTitle);
 		if(!event.navigateSuppressNavigation) {

editions/dev/tiddlers/new/Hook__th-navigating.tid

@@ -0,0 +1,19 @@
+created: 20170219130829546
+modified: 20170219145518777
+tags: HookMechanism
+title: Hook: th-navigating
+type: text/vnd.tiddlywiki
+
+This hook allows plugins to monitor and modify navigation events.
+
+Hook function parameters:
+
+* ''event'': object describing the navigation event:
+** ''event.navigateTo'': title of target tiddler
+** ''event.navigateFromTitle'': title of tiddler containing the
+** ''event.navigateSuppressNavigation'': boolean; when true the target tiddler opens without the usual scrolling
+** ''event.navigateFromClientRect'': rectange in client coordinates of the DOM node triggering the navigation
+
+Return value:
+
+* possibly modified event object