Function zp_has_filter

Check if any filter has been registered for a hook.

global array $_zp_filters storage for all of the filters

Package: core\functions\functions-filter
Author: Ozh
Located at functions-filter.php

Parameters summary
`string`	`$hook`	The name of the filter hook.
`callable`	`$function_to_check = false`	optional. If specified, return the priority of that function on this hook or false if not attached.

Return value summary
`integer\|boolean`	Optionally returns the priority on that hook for the specified function.