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function custom_exclude_on_sale_products_from_query( $q ){

	if (   $q->is_search() ) return;
	if ( ! $q->is_main_query() ) return;
	if ( ! $q->is_post_type_archive() ) return;
	if ( ! is_admin() ) {

    	$product_ids_on_sale = wc_get_product_ids_on_sale();

    	$q->set( 'post__not_in', (array) $product_ids_on_sale );

	}

}
add_action( 'woocommerce_product_query', 'custom_exclude_on_sale_products_from_query' );