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filter is not described

rewrite_rules filter-hook . WP 1.5.0

Deprecated in 1.5.0. It is no longer supported and can be removed in future releases. Use the mod_rewrite_rules filter instead.

Deprecated: 1.5.0 Use the mod_rewrite_rules filter instead.

Filters the list of rewrite rules formatted for output to an .htaccess file.

Usage

add_filter( 'rewrite_rules', 'filter_function_name_9810' );
function filter_function_name_9810( $rules ){
	// filter...

	return $rules;
}
$rules(string)
mod_rewrite Rewrite rules formatted for .htaccess.

Where the hook is called

WP_Rewrite::mod_rewrite_rules()
wp-includes/class-wp-rewrite.php 1522
return apply_filters( 'rewrite_rules', $rules );

Where the hook is used (in WP core)

Does not used.