title: How to use 'strict' mode in Chrome 'JavaScript Console'
body: <p>I am practicing JavaScript on Chrome's 'JavaScript Console' ( version: 35.0) and I am unable to use the 'use strict' clause as expected.</p>
  
  <p>For the following code snippet :</p>
  
  <pre><code>var obj={x:1,y:2}
  
  //Define new property with 'writable' flag as false.
  Object.defineProperty(obj, "z", {value:3, writable:false, enumerable:false, configurable:false})
  
  // Try to change the property 'z',
  "use strict"; obj["z"]=4
  </code></pre>
  
  <blockquote>
    <p>Output: 4</p>
  </blockquote>
  
  <p>As per my understanding, changing value of a 'non-writable' property will silently fail in non-strict mode and throw 'TypeError' in strict mode, But I don't see the exception.</p>
  
  <pre><code>console.log(obj)
  </code></pre>
  
  <blockquote>
    <p>Object {x: 1, y: 2, z: 3}</p>
  </blockquote>
  
  <p>Even though the property value is not changed but I am expecting a exception. 
  Please correct if I am doing something wrong ?</p>