# no-useless-parameters Reject common XPCOM methods called with useless optional parameters (eg. `Services.io.newURI(url, null, null)`, or non-existent parameters (eg. `Services.obs.removeObserver(name, observer, false)`). This option can be autofixed (`--fix`). ## Examples of incorrect code for this rule ```js elt.addEventListener('click', handler, false); Services.io.newURI('http://example.com', null, null); Services.obs.notifyObservers(obj, 'topic', null); ``` ## Examples of correct code for this rule ```js elt.addEventListener('click', handler); Services.io.newURI('http://example.com'); Services.obs.notifyObservers(obj, 'topic'); ```