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filter is not described

networks_clauses filter-hook . WP 4.6.0

Filters the network query clauses.

Usage

add_filter( 'networks_clauses', 'filter_function_name_4155', 10, 2 );
function filter_function_name_4155( $pieces, $this ){
	// filter...

	return $pieces;
}
$pieces(array)
A compacted array of network query clauses.
$this(WP_Network_Query)
Current instance of WP_Network_Query (passed by reference).

Where the hook is called

WP_Network_Query::get_network_ids()
wp-includes/class-wp-network-query.php 409
$clauses = apply_filters_ref_array( 'networks_clauses', array( compact( $pieces ), &$this ) );

Where the hook is used (in WP core)

Does not used.