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function is not described

_wp_object_count_sort_cb() WP 3.1.0

Serves as a callback for comparing objects based on count.

Used with uasort().

No Hooks.

Return

true/false. Whether the count value for $a is greater than the count value for $b.

Usage

_wp_object_count_sort_cb( $a, $b );
$a(object) (required)
The first object to compare.
$b(object) (required)
The second object to compare.

Code of wp object count sort cb: wp-includes/category-template.php VER 5.0.3

<?php
function _wp_object_count_sort_cb( $a, $b ) {
	return ( $a->count > $b->count );
}