title: What does ! mean in XPath 3.0?
body: <p>XPath 3.0 defines a new operator called the '<a href="http://www.w3.org/TR/xpath-30/#id-map-operator" rel="nofollow"><strong>mapping operator</strong></a>'. It is denoted by the exclamation mark --<code>!</code>. </p>
  
  <p>What does <code>A!B</code> mean? How do we use the <code>!</code> operator? Could someone give me an example?</p>