compare-func

What is compare-func?

The compare-func npm package provides a simple way to create comparator functions for sorting arrays in JavaScript. It is particularly useful when you need to sort objects based on one or more of their properties. The package allows for easy creation of comparators using property names, custom getter functions, or multiple criteria.

What are compare-func's main functionalities?

Sorting by property name

This feature allows sorting an array of objects based on a specific property. In the provided code, an array of users is sorted by the 'age' property.

const compare = require('compare-func');
let users = [
  { name: 'Alice', age: 25 },
  { name: 'Bob', age: 20 },
  { name: 'Carol', age: 30 }
];
users.sort(compare('age'));
console.log(users);

Sorting by multiple criteria

This feature enables sorting based on multiple properties. The array of users is first sorted by 'name' and then by 'age' if the names are the same.

const compare = require('compare-func');
let users = [
  { name: 'Alice', age: 25 },
  { name: 'Bob', age: 20 },
  { name: 'Carol', age: 30 }
];
users.sort(compare(['name', 'age']));
console.log(users);

Sorting using a custom getter function

This feature allows for sorting using a custom function that defines the sorting criteria. Here, users are sorted based on the length of their names.

const compare = require('compare-func');
let users = [
  { name: 'Alice', age: 25 },
  { name: 'Bob', age: 20 },
  { name: 'Carol', age: 30 }
];
users.sort(compare(u => u.name.length));
console.log(users);

Other packages similar to compare-func

lodash

Lodash is a comprehensive utility library that includes powerful sorting functions like _.sortBy and _.orderBy, which can handle multiple criteria and complex sorting logic. It is more feature-rich compared to compare-func but also larger in size.

sort-by

Sort-by is another npm package that allows for sorting arrays of objects based on property names. It is similar to compare-func but does not support custom getter functions, making it less flexible in some scenarios.

README

Get a compare function for array to sort

Install

$ npm install --save compare-func

Usage

var compareFunc = require('compare-func');

// sort by an object property
[{x: 'b'}, {x: 'a'}, {x: 'c'}].sort(compareFunc('x'));
//=> [{x: 'a'}, {x: 'b'}, {x: 'c'}]

// sort by a nested object property
[{x: {y: 'b'}}, {x: {y: 'a'}}].sort(compareFunc('x.y'));
//=> [{x: {y: 'a'}}, {x: {y: 'b'}}]

// sort by the `x` propery, then `y`
[{x: 'c', y: 'c'}, {x: 'b', y: 'a'}, {x: 'b', y: 'b'}].sort(compareFunc(['x', 'y']));
//=> [{x: 'b', y: 'a'}, {x: 'b', y: 'b'}, {x: 'c', y: 'c'}]

// sort by the returned value
[{x: 'b'}, {x: 'a'}, {x: 'c'}].sort(compareFunc(function (el) {
    return el.x;
}));
//=> [{x: 'a'}, {x: 'b'}, {x: 'c'}]

API

compareFunc([property])

Returns a compare function for array to sort

property

Type: string, function or array of the former

If missing it sorts on itself.

The string can be a dot path to a nested object property.

License

MIT © Steve Mao