title: Angular2 sibling element selector
body: <p>I wanted to hide all the previous elements, which is before <code>.map-page</code> element. </p>
  
  <p>I'm loading ionic app and I need to hide previous pages if <code>.map-page</code> is detected on the dom.</p>
  
  <p><img src="https://cloud.githubusercontent.com/assets/34341/13567460/566315da-e453-11e5-8c44-5a37410fa0a3.png" alt="image"></p>
  
  <p>in jQuery this is so simple <code>$('.map-page').siblings().hide()</code>, but in angular 2.. I'm not sure which functions to use to do that. </p>