hasFilter()
hasFilter(string $hook, callback $function_to_check = false) : integer|boolean
Check if any filter has been registered for a hook.
Parameters
| string | $hook | The name of the filter hook. |
| callback | $function_to_check | Optional. If specified, return the priority of that function/method on this hook or false if not attached. |
Returns
integer|boolean —Optionally returns the priority on that hook for the specified function/method.