// Return all last Fridays of each month in a given year
function* lastFridaysOfYear(year: number): Generator<Date, void, unknown> {
for (let month: number = 1; month <= 12; month++) {
// Last day of the month
// In JS/TS: new Date(year, month, 0) = last day of previous month
let date: Date = new Date(year, month, 0);
// Walk backward to Friday
while (date.getDay() !== 5) { // 5 = Friday
date.setDate(date.getDate() - 1);
}
yield date;
}
}
function main(): void {
const args: string[] = process.argv.slice(2);
const year: number =
args.length > 0
? parseInt(args[0], 10)
: 2026;
const formatter: Intl.DateTimeFormat =
new Intl.DateTimeFormat("en-US");
for (const date of lastFridaysOfYear(year)) {
console.log(formatter.format(date));
}
}
main();
/*
run:
1/30/2026
2/27/2026
3/27/2026
4/24/2026
5/29/2026
6/26/2026
7/31/2026
8/28/2026
9/25/2026
10/30/2026
11/27/2026
12/25/2026
*/
