- if ( isset( $m[5] ) ) {
- // enclosing tag - extra parameter
- return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, $m[5], $tag ) . $m[6];
- } else {
- // self-closing tag
- return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, null, $tag ) . $m[6];
+ /**
+ * Filters whether to call a shortcode callback.
+ *
+ * Passing a truthy value to the filter will effectively short-circuit the
+ * shortcode generation process, returning that value instead.
+ *
+ * @since 4.7.0
+ *
+ * @param bool|string $return Short-circuit return value. Either false or the value to replace the shortcode with.
+ * @param string $tag Shortcode name.
+ * @param array $attr Shortcode attributes array,
+ * @param array $m Regular expression match array.
+ */
+ $return = apply_filters( 'pre_do_shortcode_tag', false, $tag, $attr, $m );
+ if ( false !== $return ) {
+ return $return;