hron-ts (TypeScript)

Native TypeScript implementation of hron — human-readable cron expressions.

Install

npm install hron-ts

Usage

import { Schedule, Temporal } from "hron-ts";

// Parse an expression
const schedule = Schedule.parse("every weekday at 9:00 in America/New_York");

// Compute next occurrence
const now = Temporal.Now.zonedDateTimeISO();
const next = schedule.nextFrom(now);

// Compute next N occurrences
const nextFive = schedule.nextNFrom(now, 5);

// Check if a datetime matches
const matches = schedule.matches(now);

// Convert to cron (expressible subset only)
const cron = Schedule.parse("every day at 9:00").toCron();

// Convert from cron
const fromCron = Schedule.fromCron("0 9 * * *");

// Canonical string (roundtrip-safe)
console.log(schedule.toString());

Temporal Polyfill

This package uses the Temporal API via @js-temporal/polyfill. Once Temporal ships natively in runtimes, performance improves automatically. For performance-critical use cases, consider the WASM package (hron-wasm).

Tests

pnpm test

Uses vitest. Conformance tests driven by spec/tests.json.

License

MIT