Format JavaScript Array of Strings to Oxford Comma.

to-oxford-comma.md

Format JavaScript Array of Strings to Oxford Comma

const toOxfordComma = (array) =>
  array.length === 2
    ? array.join(' and ')
    : array.length > 2
    ? array
        .slice(0, array.length - 1)
        .concat(`and ${array.slice(-1)}`)
        .join(', ')
    : array.join(', ')

Usage

toOxfordComma(['Apples'])
// Apples
toOxfordComma(['Apples', 'Bananas'])
// Apples and Bananas
toOxfordComma(['Apples', 'Bananas', 'Pears'])
// Apples, Bananas, and Pears
toOxfordComma(['Apples', 'Bananas', 'Pears', 'Oranges'])
// Apples, Bananas, Pears, and Oranges

thanks for sharing this! thought i'd let you know it fails with a list of 2. ['apple', 'orange'] comes out as apple, orange but should be apple and orange.

Thanks a lot @calvin-summer, good spot.

Thanks @calvin-summer, fixed.

Hello, I believe you can just use:

const listFormatter = new Intl.ListFormat('en', { style: 'long' });
listFormatter.format(['Apples', 'Bananas', 'Pears', 'Oranges'])

Cheers

Nice, Browser support looks pretty good now too vs 2019 when I wrote this – thanks for the tip.