Function onMouse

src/uPlot.js:689–697

(ev, targ, fn, onlyTarg = true)

	const mouseListeners = new Map();

	function onMouse(ev, targ, fn, onlyTarg = true) {
		const targListeners = mouseListeners.get(targ) || {};
		const listener = cursor.bind[ev](self, targ, fn, onlyTarg);

		if (listener) {
			on(ev, targ, targListeners[ev] = listener);
			mouseListeners.set(targ, targListeners);
		}
	}

	function offMouse(ev, targ, fn) {
		const targListeners = mouseListeners.get(targ) || {};