Don’t default options to false.

README.md

@@ -92,7 +92,7 @@ const anchor = d3.select("a");
 If the *selector* is not a string, instead selects the specified node; this is useful if you already have a reference to a node, such as `this` within an event listener or a global such as `document.body`. For example, to make a clicked paragraph red:
 
 ```js
-d3.selectAll("p").on("click", function() {
+d3.selectAll("p").on("click", function(event) {
   d3.select(this).style("color", "red");
 });
 ```
@@ -654,16 +654,14 @@ For interaction, selections allow listening for and dispatching of events.
 
 Adds or removes a *listener* to each selected element for the specified event *typenames*. The *typenames* is a string event type, such as `click`, `mouseover`, or `submit`; any [DOM event type](https://developer.mozilla.org/en-US/docs/Web/Events#Standard_events) supported by your browser may be used. The type may be optionally followed by a period (`.`) and a name; the optional name allows multiple callbacks to be registered to receive events of the same type, such as `click.foo` and `click.bar`. To specify multiple typenames, separate typenames with spaces, such as `input change` or `click.foo click.bar`.
 
-When a specified event is dispatched on a selected element, the specified *listener* will be evaluated for the element, being passed the current datum (*d*), the current index (*i*), and the current group (*nodes*), with *this* as the current DOM element (*nodes*[*i*]). Listeners always see the latest datum for their element, but the index is a property of the selection and is fixed when the listener is assigned; to update the index, re-assign the listener. To access the current event within a listener, use [d3.event](#event).
+When a specified event is dispatched on a selected element, the specified *listener* will be evaluated for the element, being passed the current event (*event*) and the current datum (*d*), with *this* as the current DOM element (*event*.currentTarget). Listeners always see the latest datum for their element. Note: while you can use [*event*.pageX](https://developer.mozilla.org/en/DOM/event.pageX) and [*event*.pageY](https://developer.mozilla.org/en/DOM/event.pageY) directly, it is often convenient to transform the event position to the local coordinate system of the element that received the event using [d3.clientPoint](#clientPoint).
 
 If an event listener was previously registered for the same *typename* on a selected element, the old listener is removed before the new listener is added. To remove a listener, pass null as the *listener*. To remove all listeners for a given name, pass null as the *listener* and `.foo` as the *typename*, where `foo` is the name; to remove all listeners with no name, specify `.` as the *typename*.
 
 An optional *options* object may specify characteristics about the event listener, such as whether it is capturing or passive; see [*element*.addEventListener](https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/addEventListener).
 
 If a *listener* is not specified, returns the currently-assigned listener for the specified event *typename* on the first (non-null) selected element, if any. If multiple typenames are specified, the first matching listener is returned.
 
-Note: while you can use [*event*.pageX](https://developer.mozilla.org/en/DOM/event.pageX) and [*event*.pageY](https://developer.mozilla.org/en/DOM/event.pageY) directly, it is often more convenient to transform the event position to the local coordinate system of the element that received the event using [d3.clientPoint](#clientPoint).
-
 <a name="selection_dispatch" href="#selection_dispatch">#</a> <i>selection</i>.<b>dispatch</b>(<i>type</i>[, <i>parameters</i>]) [<>](https://github.com/d3/d3-selection/blob/master/src/selection/dispatch.js "Source")
 
 Dispatches a [custom event](http://www.w3.org/TR/dom/#interface-customevent) of the specified *type* to each selected element, in order. An optional *parameters* map may be specified to set additional properties of the event. It may contain the following fields:

src/selection/on.js

@@ -18,7 +18,7 @@ function onRemove(typename) {
     if (!on) return;
     for (var j = 0, i = -1, m = on.length, o; j < m; ++j) {
       if (o = on[j], (!typename.type || o.type === typename.type) && o.name === typename.name) {
-        this.removeEventListener(o.type, o.listener, o.capture);
+        this.removeEventListener(o.type, o.listener, o.options);
       } else {
         on[++i] = o;
       }
@@ -28,25 +28,25 @@ function onRemove(typename) {
   };
 }
 
-function onAdd(typename, value, capture) {
-  return function(d, i, group) {
-    var on = this.__on, o, listener = contextListener(value, i, group);
+function onAdd(typename, value, options) {
+  return function() {
+    var on = this.__on, o, listener = contextListener(value);
     if (on) for (var j = 0, m = on.length; j < m; ++j) {
       if ((o = on[j]).type === typename.type && o.name === typename.name) {
-        this.removeEventListener(o.type, o.listener, o.capture);
-        this.addEventListener(o.type, o.listener = listener, o.capture = capture);
+        this.removeEventListener(o.type, o.listener, o.options);
+        this.addEventListener(o.type, o.listener = listener, o.options = options);
         o.value = value;
         return;
       }
     }
-    this.addEventListener(typename.type, listener, capture);
-    o = {type: typename.type, name: typename.name, value: value, listener: listener, capture: capture};
+    this.addEventListener(typename.type, listener, options);
+    o = {type: typename.type, name: typename.name, value: value, listener: listener, options: options};
     if (!on) this.__on = [o];
     else on.push(o);
   };
 }
 
-export default function(typename, value, capture) {
+export default function(typename, value, options) {
   var typenames = parseTypenames(typename + ""), i, n = typenames.length, t;
 
   if (arguments.length < 2) {
@@ -62,7 +62,6 @@ export default function(typename, value, capture) {
   }
 
   on = value ? onAdd : onRemove;
-  if (capture == null) capture = false;
-  for (i = 0; i < n; ++i) this.each(on(typenames[i], value, capture));
+  for (i = 0; i < n; ++i) this.each(on(typenames[i], value, options));
   return this;
 }