In this Article we will go through how to count the occurrences of a value in an array only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const countOccurrences = (arr, val) => arr.reduce((a, v) => (v === val ? a + 1 : a), 0);

In this Article we will go through how to count the occurrences of array elements only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const countOccurrences = arr => arr.reduce((prev, curr) => (prev[curr] = ++prev[curr] || 1, prev), {});

In this Article we will go through how to create an array of cumulative sum only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const accumulate = arr => arr.map((sum => value => sum += value)(0));

In this Article we will go through how to create an array of numbers in the given range only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const range = (min, max) => [...Array(max - min + 1).keys()].map(i => i + min);

In this Article we will go through how to create cartesian product only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const cartesian = (...sets) => sets.reduce((acc, set) => acc.flatMap((x) => set.map((y) => [...x, y])), [[]]);

In this Article we will go through how to empty an array only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const empty = arr => arr.length = 0;

In this Article we will go through how to find the closest number from an array only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

// Find the number from `arr` which is closest to `n`
const closest = (arr, n) => arr.reduce((prev, curr) => Math.abs(curr - n) < Math.abs(prev - n) ? curr : prev);

In this Article we will go through how to find the index of the last matching item of an array only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const lastIndex = (arr, predicate) => arr.reduce((prev, curr, index) => predicate(curr) ? index : prev, -1);

In this Article we will go through how to find the index of the maximum item of an array only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const indexOfMax = arr => arr.reduce((prev, curr, i, a) => curr > a[prev] ? i : prev, 0);

In this Article we will go through how to find the index of the minimum item of an array only using single line of code in JavaScript. This is a one-line JavaScript code snippet that uses one of the most popular ES6 features => Arrow Function.

Let's define this short function:

const indexOfMin = arr => arr.reduce((prev, curr, i, a) => curr < a[prev] ? i : prev, 0);