一段诡异的代码，没理解

var cableProjectAddressBList = [];
function getCableProjectAddressBList(cableTypeCode, cableId, cableAPositionName) {
    
    cableAPositionName = encodeURIComponent(cableAPositionName);
    if (cableTypeCode && cableId && cableAPositionName) {

        $.ajax({
            dataType: "json",
            url: "ajax.aspx",
            data: {
                operationType: 'getCableProjectAddressBList',
                cableTypeCode: cableTypeCode,
                cableId: cableId,
                cableAPositionName: cableAPositionName
            },
            success: function (data, textStatus, jqXHR) {
                var cableProjectAddressBList = [];
function