chrono

This is a ported version of https://github.com/wanasit/chrono typescript library

Caution: super slow in debug mode(idk why), but in release it is good

all tests rewritten and passed

It is designed to handle most date/time format and extract information from any given text:

• Today, Tomorrow, Yesterday, Last Friday, etc
• 17 August 2013 - 19 August 2013
• This Friday from 13:00 - 16.00
• 5 days ago
• 2 weeks from now
• Sat Aug 17 2013 18:40:39 GMT+0900 (JST)
• 2014-11-30T08:15:30-05:30

Languages

english, russian

usage

vanilla version(same answers as original lib)

  chrono:
    git:
      url: https://github.com/SibirixScrum/dart-chrono.git
      ref: '1.0v'

our custom version

  chrono:
    git:
      url: https://github.com/SibirixScrum/dart-chrono.git
      ref: '1.0s'

parsing

  final result = Chrono.en.casual.parse('An appointment on Sep 12-13'); // now is 2023-09-29
  print(result[0].start.date()); // 2023-09-12 12:00:00.000
  print(result[0].end?.date()); // 2023-09-13 12:00:00.000

you can also pass PasringOption and ParsingReference

  final result = Chrono.en.casual.parse('An appointment on Sep 12-13',referenceDate: DateTime(2025,9,20));
  // Fri Sep 12 2014 12:00:00 GMT-0500 (CDT)
  print(result[0].start.date()); // 2025-09-12 12:00:00.000
  print(result[0].end?.date()); // 2025-09-13 12:00:00.000

  final result = Chrono.en.casual.parse('An appointment on Sep 12-13',referenceDate: DateTime(2025,9,20),option: ParsingOption(forwardDate: true));
  // Fri Sep 12 2014 12:00:00 GMT-0500 (CDT)
  print(result[0].start.date()); // 2026-09-12 12:00:00.000
  print(result[0].end?.date()); // 2026-09-13 12:00:00.000

ParsingReference

you can simply pass DateTime or use ParsingReference class

• instant?: Date The instant when the input is written or mentioned
• timezone?: string | number The timezone where the input is written or mentioned. Support minute-offset (number) and timezone name (e.g. "GMT", "CDT"). You can see all suported strings in file timezone.dart

ParsingOption

forwardDate (boolean) to assume the results should happen after the reference date (forward into the future) timezones Override or add custom mappings between timezone abbreviations and offsets. Use this when you want Chrono to parse certain text into a given timezone offset. Chrono supports both unambiguous (normal) timezone mappings and ambigous mappings where the offset is different during and outside of daylight savings.

ParsedResult

• refDate: Date The reference date of this result
• index: number The location within the input text of this result
• text: string The text this result that appears in the input
• start: ParsedComponents The parsed date components as a ParsedComponents object
• end?: ParsedComponents Similar to start
• date: () => Date Create a dart DateTime for start

ParsedComponents

• get: (c: Component) => number | null Get known or implied value for the component
• isCertain: (c: Component) => boolean Check if the component has a known value
• date: () => Date Create a dart DateTime
• if you want more information you can use ParsedComponents as ParsingComponent and get a bunch of extra properties

More information

check original https://github.com/wanasit/chrono