Update snippet descriptions

snippets/differenceWith.md

@@ -6,11 +6,14 @@ tags: array,intermediate
 Filters out all values from an array for which the comparator function does not return `true`.
 
 - Use `Array.prototype.filter()` and `Array.prototype.findIndex()` to find the appropriate values.
+- Omit the last argument, `comp`, to use a default strict equality comparator.
 
 ```js
-const differenceWith = (arr, val, comp) => arr.filter(a => val.findIndex(b => comp(a, b)) === -1);
+const differenceWith = (arr, val, comp = (a, b) => a === b) =>
+  arr.filter(a => val.findIndex(b => comp(a, b)) === -1);
 ```
 
 ```js
 differenceWith([1, 1.2, 1.5, 3, 0], [1.9, 3, 0], (a, b) => Math.round(a) === Math.round(b)); // [1, 1.2]
+differenceWith([1, 1.2, 1.3], [1, 1.3, 1.5]); // [1.2]
 ```