Francesco Fortunati fortwo

👨‍💻 Frontend dev obsessed with #JavaScript and its ecosystem 🏃‍♂️ Running junkie 🇪🇸 Spain lover 🌅 Always chasing the perfect sunset

fortwo / groupByMultipleKeys.js

Last active November 26, 2020 21:10

Based on the very well written https://gist.github.com/robmathers/1830ce09695f759bf2c4df15c29dd22d, this is a groupBy method that supports multiple keys.

	const groupBy = (data, keys) => { // `data` is an array of objects, `keys` is the array of keys (or property accessor) to group by
	// reduce runs this anonymous function on each element of `data` (the `item` parameter,
	// returning the `storage` parameter at the end
	return data.reduce((storage, item) => {
	// returns an object containing keys and values of each item
	const groupValues = keys.reduce((values, key) => {
	values[key] = item[key];
	return values;
	}, {});

fortwo / groupBy.js

Created June 22, 2020 12:45

A more readable and annotated version of the Javascript groupBy from Ceasar Bautista (https://stackoverflow.com/a/34890276/1376063)

	const groupBy = (data, keys) => { // `data` is an array of objects, `keys` is the array of keys (or property accessor) to group by
	// reduce runs this anonymous function on each element of `data` (the `item` parameter,
	// returning the `storage` parameter at the end
	return data.reduce((storage, item) => {
	//
	const groupValues = keys.reduce((values, key) => {
	values[key] = item[key];
	return values;
	}, {});