Implementing Temporal API

The Temporal API provides a modern, more capable date/time API for JavaScript. Let's explore how to implement this powerful feature effectively.

Understanding Temporal API

The Temporal API offers several advantages over the traditional Date object:

• Immutable date/time objects
• Timezone-aware operations
• Calendar system support
• Precise duration calculations
• Type-safe operations

Basic Implementation

1. Creating Temporal Objects

Work with different temporal types:

// Current date in local calendar
const now = Temporal.Now.plainDateTimeISO();

// Specific date and time
const meeting = Temporal.PlainDateTime.from({
  year: 2025,
  month: 1,
  day: 15,
  hour: 9,
  minute: 30
});

// Date only
const deadline = Temporal.PlainDate.from('2025-03-01');

// Time only
const dailyStandup = Temporal.PlainTime.from('09:00');

2. Basic Operations

Perform common date/time operations:

// Add duration
const futureDate = now.add({
  days: 7,
  hours: 2,
  minutes: 30
});

// Subtract duration
const pastDate = now.subtract({ days: 5 });

// Compare dates
const isAfter = futureDate.compare(pastDate) > 0;

// Format output
console.log(now.toString()); // 2025-01-03T08:54:41
console.log(now.toLocaleString()); // 1/3/2025, 8:54:41 AM

Advanced Features

1. Timezone Handling

Work with different timezones:

class TimezoneManager {
  constructor() {
    this.timeZone = Temporal.Now.timeZone();
  }

  convertToTimezone(dateTime, targetZone) {
    return dateTime.toZonedDateTime(targetZone);
  }

  getCurrentOffset(zone) {
    const now = Temporal.Now.instant();
    return Temporal.TimeZone.from(zone)
      .getOffsetStringFor(now);
  }

  getAvailableTimezones() {
    return Temporal.TimeZone.getAvailableTimeZones();
  }
}

// Usage example
const tzManager = new TimezoneManager();
const meeting = Temporal.PlainDateTime.from({
  year: 2025,
  month: 1,
  day: 15,
  hour: 9,
  minute: 0
});

const tokyoMeeting = tzManager.convertToTimezone(
  meeting,
  'Asia/Tokyo'
);

2. Calendar Systems

Support different calendar systems:

class CalendarManager {
  constructor(calendar = 'iso8601') {
    this.calendar = Temporal.Calendar.from(calendar);
  }

  convertDate(date, targetCalendar) {
    return date.withCalendar(targetCalendar);
  }

  getMonthsInYear(year) {
    return this.calendar.monthsInYear(year);
  }

  getDaysInMonth(year, month) {
    return this.calendar.daysInMonth(year, month);
  }
}

// Usage with different calendars
const hebrewCalendar = new CalendarManager('hebrew');
const islamicCalendar = new CalendarManager('islamic');

Working with Durations

1. Duration Calculations

Handle time durations effectively:

class DurationCalculator {
  static calculate(start, end) {
    return start.until(end);
  }

  static format(duration) {
    return duration.toString({
      style: 'long',
      maximumFractionDigits: 0
    });
  }

  static humanReadable(duration) {
    const parts = [];

    if (duration.years) parts.push(`${duration.years} years`);
    if (duration.months) parts.push(`${duration.months} months`);
    if (duration.days) parts.push(`${duration.days} days`);
    if (duration.hours) parts.push(`${duration.hours} hours`);
    if (duration.minutes) parts.push(`${duration.minutes} minutes`);

    return parts.join(', ');
  }
}

2. Scheduling

Implement scheduling functionality:

class Scheduler {
  constructor() {
    this.events = new Map();
  }

  addEvent(title, startTime, duration) {
    const endTime = startTime.add(duration);

    this.events.set(title, {
      start: startTime,
      end: endTime,
      duration
    });
  }

  findOverlaps(event) {
    const overlaps = [];

    for (const [title, existing] of this.events) {
      if (this.isOverlapping(event, existing)) {
        overlaps.push(title);
      }
    }

    return overlaps;
  }

  isOverlapping(event1, event2) {
    return event1.start < event2.end && 
           event1.end > event2.start;
  }
}

Performance Optimization

1. Caching Calculations

Implement efficient caching:

class TemporalCache {
  constructor() {
    this.cache = new Map();
    this.maxSize = 1000;
  }

  getCacheKey(operation, ...args) {
    return `${operation}:${args.join(':')}`;
  }

  get(operation, ...args) {
    return this.cache.get(
      this.getCacheKey(operation, ...args)
    );
  }

  set(operation, result, ...args) {
    if (this.cache.size >= this.maxSize) {
      const firstKey = this.cache.keys().next().value;
      this.cache.delete(firstKey);
    }

    this.cache.set(
      this.getCacheKey(operation, ...args),
      result
    );
  }
}

2. Batch Operations

Handle multiple operations efficiently:

class BatchProcessor {
  constructor() {
    this.operations = [];
  }

  addOperation(fn, ...args) {
    this.operations.push({ fn, args });
  }

  async process() {
    const results = [];

    for (const { fn, args } of this.operations) {
      try {
        const result = await fn(...args);
        results.push(result);
      } catch (error) {
        results.push({ error });
      }
    }

    this.operations = [];
    return results;
  }
}

Error Handling

1. Validation

Implement robust validation:

class TemporalValidator {
  static validateDate(date) {
    try {
      return Temporal.PlainDate.from(date);
    } catch (error) {
      throw new Error(`Invalid date: ${date}`);
    }
  }

  static validateTime(time) {
    try {
      return Temporal.PlainTime.from(time);
    } catch (error) {
      throw new Error(`Invalid time: ${time}`);
    }
  }

  static validateTimeZone(zone) {
    try {
      return Temporal.TimeZone.from(zone);
    } catch (error) {
      throw new Error(`Invalid timezone: ${zone}`);
    }
  }
}

2. Error Recovery

Handle error cases gracefully:

class ErrorHandler {
  static handleInvalidInput(input, fallback) {
    try {
      return Temporal.PlainDateTime.from(input);
    } catch {
      console.warn(`Invalid input: ${input}, using fallback`);
      return fallback;
    }
  }

  static handleTimeZoneError(zone, fallback = 'UTC') {
    try {
      return Temporal.TimeZone.from(zone);
    } catch {
      console.warn(`Invalid timezone: ${zone}, using ${fallback}`);
      return Temporal.TimeZone.from(fallback);
    }
  }
}

Best Practices

1. Immutability

• Always treat Temporal objects as immutable
• Use appropriate methods for modifications
• Store new values in new variables

1. Timezone Handling

• Always be explicit about timezones
• Handle timezone conversions carefully
• Consider DST transitions

1. Performance

• Cache frequently used calculations
• Batch operations when possible
• Handle large datasets efficiently

Conclusion

The Temporal API provides powerful tools for date/time handling:

1. Benefits

• Improved accuracy
• Better timezone support
• Calendar system flexibility
• Type safety

1. Implementation Tips

• Use appropriate types
• Handle errors properly
• Consider performance
• Maintain immutability

1. Best Practices

• Validate input
• Handle edge cases
• Document assumptions
• Test thoroughly

Remember to:

• Keep operations immutable
• Handle timezones explicitly
• Validate input data
• Consider performance implications