code: func ForceNewIfChange(key string, f ValueChangeConditionFunc) schema.CustomizeDiffFunc {
  	return func(d *schema.ResourceDiff, meta interface{}) error {
  		old, new := d.GetChange(key)
  		if f(old, new, meta) {
  			d.ForceNew(key)
  		}
  		return nil
  	}
  }
docs: // ForceNewIfChange returns a CustomizeDiffFunc that flags the given key as
  // requiring a new resource if the given condition function returns true.
  //
  // The return value of the condition function is ignored if the old and new
  // values compare equal, since no attribute diff is generated in that case.
  //
  // This function is similar to ForceNewIf but provides the condition function
  // only the old and new values of the given key, which leads to more compact
  // and explicit code in the common case where the decision can be made with
  // only the specific field value.