gistfile1.txt

const windowManager = imports.ui.windowManager;

let popup;

function init() {
    popup = windowManager.WindowManager.prototype['_showWorkspaceSwitcher'];
}

function enable() {
    windowManager.WindowManager.prototype['_showWorkspaceSwitcher'] = function(a,b,c){return 42};
}

function disable() {
    windowManager.WindowManager.prototype['_showWorkspaceSwitcher'] = popup;
}