You've seen how to use the sortBy() method to negate a value so that you can sort in descending order. The sortBy() method is also useful when you need to sort by more complex data and sort criteria. Even the sortBy() method has its limitations with respect to sorting lists of maps; so, you have to think about alternative approaches here.
The sortBy() method uses the default greater than and less than comparator function—the same default used by sort(). The function that is passed to sortBy() is called an iteratee, which is a function that's used to produce values that are fed into the comparator function. This is useful when you want to use the default comparator—writing iteratees is easier than customizing comparator functions.
Note
If it turns out that you've written an iteratee function and you have a reusable comparator function, you can use both. The sortBy() method accepts a comparator as its second argument.
Let's start by writing a simple utility...