title: Creating an angular directive for changing placeholder text for a form
body: <p>This isn't a direct coding question per se...more like what is the best practice or the smartest way to go about something like this.</p>
  
  <p>I have a form with a button that should change placeholder text to the custom error if the input is invalid. So basically "on click" should the validity be checked. </p>
  
  <p>Would I just surround the whole form in a directive and loop through each field when the button is clicked and check validity? My other solution included making a directive for each input and not include the button, but somehow interact with the form through the use of a parent scope when the button is clicked. </p>