PhantomJS evaluateJavascript()

evaluateJavaScript(str);

var wpage = require('webpage').create(); 
wpage.open('http://localhost/tasks/test.html', function(status) { 
   var script1 = "function(){ var a = document.title; return a;}"; 
   var value = wpage.evaluateJavaScript(script1); 
   console.log(value); 
   phantom.exit(); 
});

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