WordPress at a glance
filter is not described

(permastructname)_rewrite_rules filter-hook . WP 3.1.0

Filters rewrite rules used for individual permastructs.

The dynamic portion of the hook name, $permastructname, refers to the name of the registered permastruct, e.g. 'post_tag' (tags), 'category' (categories), etc.

Usage

add_filter( '(permastructname)_rewrite_rules', 'filter_function_name_2873' );
function filter_function_name_2873( $rules ){
	// filter...

	return $rules;
}
$rules(array)
The rewrite rules generated for the current permastruct.

Where the hook is called

WP_Rewrite::rewrite_rules()
wp-includes/class-wp-rewrite.php 1367
$rules = apply_filters( "{$permastructname}_rewrite_rules", $rules );

Where the hook is used (in WP core)

Does not used.