javascript - Webdriverjs - By is not defined -

i using webdriverjs, open website , select element id. code is,

var webdriverjs = require('webdriverjs'),     client      = webdriverjs.remote({desiredcapabilities:{browsername:'phantomjs'}}).init();  client.url('www.google.com', function(err){   client.findelement(webdriverjs.by.id('lst-ib')).sendkeys('duck duck go\n') }) 

it throws error as,

webdriverjs.by undefined 

how use by function in webdriverjs?

i think can still use webdriverjs, example code has mistake

https://code.google.com/p/selenium/wiki/webdriverjs

the code in example

driver.findelement(by.name("q")).sendkeys("webdriver");

driver.findelement(by.name("btng")).click();

should

driver.findelement(webdriver.by.name("q")).sendkeys("webdriver");

driver.findelement(webdriver.by.name("btng")).click();

i not sure why incorrect on website.