How can I establish a predetermined sort order in JavaScript?

Other Questions JavaScript
1

I’m looking for guidance because my research hasn’t provided a clear solution yet. I need to reorder an array made up of objects, each having a status property. Specifically, I want objects with the status ‘END’ to appear first, followed by those with ‘PREP’, and so on down a defined sequence.

Below is an example code snippet demonstrating a similar concept with alternative variable names:

const itemsList = [
  { category: 'NEW' },
  { category: 'PREP' },
  { category: 'CLOS' },
  { category: 'END' },
  { category: 'ERR' },
  { category: 'PAUS' }
];

const sortPriority = ['END', 'PREP', 'NEW', 'CLOS', 'ERR', 'PAUS'];

itemsList.sort((item1, item2) => sortPriority.indexOf(item1.category) - sortPriority.indexOf(item2.category));

console.log(itemsList);

Can anyone suggest if there is a more efficient or idiomatic way in JavaScript to implement such a fixed ordering mechanism?

2

I solved a similar problem by creating a lookup object that assigned numeric values to each status, which allowed me to compare the items in O(1) time for each comparison. This approach removed the need for linear indexOf calls during sorting, especially as the list expanded. In my experience, this slight restructuring of the data significantly improved performance in cases with a large array. Additionally, it improved overall code clarity by clearly associating each status with its respective sort order.

3

Another approach that works well is to embed the ordering value directly into each object. For instance, adding an additional property that holds the predetermined sort order can shift the heavy work away from the sorting function. In practice, this means you only calculate the sort value once when objects are created rather than computing it repeatedly during each comparison. Although it slightly increases memory usage due to the extra field, I found that the overall performance improved with large arrays. This method also results in clearer code because the order is explicit within each object.

4

i tried a trick by setting the order value in each obj during creation. this way you avoid a repetitive lookup in sort. it’s simple and effective even if it uses a bit more memry. worth a shot if you want to preassign the priorities.

5

One alternative that I found effective involves using a constant mapping created once outside your sort function. Instead of repeatedly calling a lookup like indexOf in each comparison, you can define an immutable object that maps each status to its sorting weight. In my project, this method not only made the sort callback more readable but also reduced the potential overhead in larger arrays. I observed that by referencing this mapping within the sort comparator via property access, the code was both maintainable and demonstrably faster in practice.