ESP8266 module name

Ok, start from the beginning. At last flashed boot 1.6 and 1.91 firmware but this code doesn`t work

var wifi = require("Wifi");

console.log ("START");

wifi.connect ("mySSID", {password:"myPWD"}, function (){
console.log ("Connected to ap");
}
);


wifi.setIP ({ip:"192.168.1.50", gw:"192.168.1.1", netmask:"255.155.255.0"}, function (){
console.log ("Ip set");
}
);

ESP stays in default AP mode, doesnt connect to "mySSID" AP and cant find wifi.setIP function

 _____                 _ 
|   __|___ ___ ___ _ _|_|___ ___ 
|   __|_ -| . |  _| | | |   | . |
|_____|___|  _|_| |___|_|_|_|___|
          |_| http://espruino.com
 1v91 Copyright 2016 G.Williams

Espruino is Open Source. Our work is supported
only by sales of official boards and donations:
http://espruino.com/Donate
Flash map 1MB:512/512, manuf 0xe0 chip 0x4014

START
Uncaught Error: Function "setIP" not found!
 at line 1 col 167
wifi.setIP ({ip:"192.168.1.50", gw:"192.168.1.1", netmask:"2...
                              ^
=undefined
>

The IDE warns that Wifi module not found. Where is it located?