define(function() {
  
  function addGetHookIf( conditionFn, hookFn ) {
  	// Define the hook, we'll check on the first run if it's really needed.
  	return {
  		get: function() {
  			var condition = conditionFn();
  
  			if ( condition == null ) {
  				// The test was not ready at this point; screw the hook this time
  				// but check again when needed next time.
  				return;
  			}
  
  			if ( condition ) {
  				// Hook not needed (or it's not possible to use it due to missing dependency),
  				// remove it.
  				// Since there are no other hooks for marginRight, remove the whole object.
  				delete this.get;
  				return;
  			}
  
  			// Hook needed; redefine it so that the support test is not executed again.
  
  			return (this.get = hookFn).apply( this, arguments );
  		}
  	};
  }
  
  return addGetHookIf;
  
  });