function register()

in ArticleTemplates/assets/js/modules/messenger.js [25:43]

• 16 lines of code
• 6 McCabe index (conditional complexity)

function register(type, callback, options) {
    options || (options = {});

    if (registeredListeners === 0) {
        on(window);
    }

    /* Persistent listeners are exclusive */
    if (options.persist) {
        listeners[type] = callback;
        registeredListeners += 1;
    } else {
        listeners[type] || (listeners[type] = []);
        if (!listeners[type].includes(callback)) {
            listeners[type].push(callback);
            registeredListeners += 1;
        }
    }
}