chronical

A high-performance implementation of RRule (RFC 5545) using the Temporal API, written in Rust with Node.js bindings.

The name chronical comes from chrono (a Rust crate for handling date and time) and iCalendar (RFC 5545).

Installation

npm install chronical

Quick Start

import { RRuleSet } from "chronical";

const rruleSet = RRuleSet.fromString(
  "DTSTART;TZID=Asia/Tokyo:20250101T000000\nRRULE:FREQ=DAILY;COUNT=3",
);

// Get all occurrences
const dates = rruleSet.all();
console.log(dates.map((d) => d.toString()));
// [
//   "2025-01-01T00:00:00+09:00[Asia/Tokyo]",
//   "2025-01-02T00:00:00+09:00[Asia/Tokyo]",
//   "2025-01-03T00:00:00+09:00[Asia/Tokyo]",
// ]

License

MIT