Valid JS, not valid for Espruino

Here's the code before minifying.

;(function(){
  var WIFI_NAME = "XXXXXX";
  var WIFI_PASS = "XXXXXX";
  var MQTT_HOST = "192.168.1.145";

  var mqtt, wifi;

  mqtt = __non_webpack_require__("MQTT");
  wifi = __non_webpack_require__("EspruinoWiFi");­

  var client = mqtt.create(MQTT_HOST);

  client.on('connected', function() {
    client.subscribe("root/branch");
  });

  client.on('publish', function(pub) {
    console.log("topic: "+pub.topic);
    console.log("message: "+pub.message);
  });

  wifi.connect(WIFI_NAME, { password: WIFI_PASS }, function(err) {
    if (err) {
      console.log("Connection error: "+err);
      return;
    }
    console.log("Connected!");
    client.connect();
  });
})();