title: How to switch php version when running composer?
body: <p>I have composer installed on windows 8.1. I use it to download drupal distributions and modules. I have also installed acquia dev desktop. As you know that dev desktop comes with different versions of php and it has separate folders for it. I have setup composer to use php 5.6. How can I make it use php 7?</p>
  
  <p>Should I uninstall composer and install again or what?</p>