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+/** Mitt: Tiny (~200b) functional event emitter / pubsub.
+ *	@name mitt
+ *	@returns {Mitt}
+ */
+export default function mitt(all) {
+	// Arrays of event handlers, keyed by type
+	all = all || {};
+
+	// Get or create a named handler list
+	function list(type) {
+		let t = type.toLowerCase();
+		return all[t] || (all[t] = []);
+	}
+
+	return {
+
+		/** Register an event handler for the given type.
+		 *	@param {String} type		Type of event to listen for, or `"*"` for all events
+		 *	@param {Function} handler	Function to call in response to the given event
+		 *	@memberof mitt
+		 */
+		on(type, handler) {
+			list(type).push(handler);
+		},
+
+		/** Remove an event handler for the given type.
+		 *	@param {String} type		Type of event to unregister `handler` from, or `"*"`
+		 *	@param {Function} handler	Handler function to remove
+		 *	@memberof mitt
+		 */
+		off(type, handler) {
+			let e = list(type),
+				i = e.indexOf(handler);
+			if (~i) e.splice(i, 1);
+		},
+
+		/** Invoke all handlers for the given type.
+		 *	If present, `"*"` handlers are invoked prior to type-matched handlers.
+		 *	@param {String} type	The event type to invoke
+		 *	@param {Any} [event]	An event object, passed to each handler
+		 *	@memberof mitt
+		 */
+		emit(type, event) {
+			list('*').concat(list(type)).forEach( f => { f(event); });
+		}
+	};
+}