Check if any action has been registered for a hook.


has_action( $tag, $function_to_check = false )
 (string) The name of the action hook.
 (callback|boolean) Optional. The callback to check for. Default false.
Default: false


(boolean|int) If $function_to_check is omitted, returns boolean for whether the hook has anything registered. When checking a specific function, the priority of that hook is returned, or false if the function is not attached. When using the $function_to_check argument, this function may return a non-boolean value that evaluates to false (e.g.) 0, so use the === operator for testing the return value.


function has_action($tag, $function_to_check = false) {
	return has_filter($tag, $function_to_check);
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