Angularjs orderBy: how to call default comparator from custom sort function - angularjs

Question

I have a custom sort function to convert strings to numbers for one column in a grid. The other columns are comprised of strings or date values. I have a custom sort function which checks for the number column and performs the conversion, but for the other values I want the default comparator's behavior. How do I achieve this?
$scope.sort = function (keyname) {
$scope.sortKey = keyname;
$scope.reverse = !$scope.reverse;
};
$scope.sortSubGrid = function (a, b) {
if ($scope.sortKey === 'caseNumber') {
return = parseInt(b.value) -parseInt(a.value);
}
else {
return = a.value > b.value;
}
};
<tr dir-paginate="agreement in agreements|orderBy:sortKey:reverse:sortSubGrid" ...>
The second half of the sortSubGrid function is intended to sort the non-numeric columns, but isn't achieving the results I expect, which is simply the results the default comparator provides. How do I get the default behavior for this second clause?

Answer 1

According to the code in orderBy.js you can use either the default or the custom but no both as you describe, it would be a nice functionality though.
// Define the `compare()` function. Use a default comparator if none is specified.
var compare = isFunction(compareFn) ? compareFn : defaultCompare;
So you can always get the original defaultCompare code and modify it.
// source orderBy.js
function defaultCompare(v1, v2) {
var result = 0;
var type1 = v1.type;
var type2 = v2.type;
if (type1 === type2) {
var value1 = v1.value;
var value2 = v2.value;
if (type1 === 'string') {
// Compare strings case-insensitively
value1 = value1.toLowerCase();
value2 = value2.toLowerCase();
} else if (type1 === 'object') {
// For basic objects, use the position of the object
// in the collection instead of the value
if (isObject(value1)) value1 = v1.index;
if (isObject(value2)) value2 = v2.index;
}
if (value1 !== value2) {
result = value1 < value2 ? -1 : 1;
}
} else {
result = type1 < type2 ? -1 : 1;
}
return result;
}