Following tries do not work:
/* tslint:disable:\"no-unused-variable\" */
/* tslint:disable:\'no-unused-variable\' */
/* tslint:disable:no-unused-variable *
This warning doesn't come from TSLint, so configuring TSLint won't help here. This is WebStorm own inspection error. You can either disable this inspection or suppress it for current statement: hit Alt+Enter on 'isDone', then hit Right and choose the appropriate action from the popup. See https://www.jetbrains.com/help/webstorm/2016.1/suppressing-inspections.html#1