php sort

sort.php

<?php 

function sort_nested_arrays( $array, $args = array('votes' => 'desc') ){
	usort( $array, function( $a, $b ) use ( $args ){
		$res = 0;

		$a = (object) $a;
		$b = (object) $b;

		foreach( $args as $k => $v ){
			if( $a->$k == $b->$k ) continue;

			$res = ( $a->$k < $b->$k ) ? -1 : 1;
			if( $v=='desc' ) $res= -$res;
			break;
		}

		return $res;
	} );

	return $array;
}


    function sort_meta_index_start($a, $b)
    {
       $start_sort_a =  get_post_meta($a->ID, 'start_sort', 1);
       $start_sort_b =  get_post_meta($b->ID, 'start_sort', 1);
      if(empty($start_sort_a)){
        $start_sort_a = 'zzzzzzzzzzzzz';
      }      
      if(empty($start_sort_b)){
        $start_sort_b = 'zzzzzzzzzzzzz';
      }
       
        if ($start_sort_a == $start_sort_b) {
            return 0;
        }
        return ($start_sort_a < $start_sort_b) ? -1 : 1;
    }

    usort($prop_selection->posts, "sort_meta_index_start");