Solution to @cassidoo's interview question of the week 2024-12-30

newYearsDay.js

// Interview question of the week (see https://buttondown.com/cassidoo/archive/we-must-adjust-to-changing-times-and-still-hold/)
// ...
// 
// This week's question:
// Given a year, return the day of the week for New Year's Day of that year.
// 
// Example:
// 
// > newYearsDay(2025)
// > "Wednesday"
// 
// > newYearsDay(2024)
// > "Monday"
// (you can submit your answers by replying to this email with a link to your solution, or share on Bluesky, Twitter, LinkedIn, or Mastodon)
function newYearsDay(year) {
    return new Date(year, 0, 1).toLocaleString(window.navigator.language, { weekday: 'long' })
}