/edtf-converter

Allows converting between natural language, EDTF compliant date strings and JS/Moment dates.

Primary LanguageTypeScript

EDTF Converter

Allows converting between natural language, EDTF compliant date strings and Moment.js dates.

Installation

$ npm install edtf-converter

Usage

Node.js (CommonJS)

const { Converter } = require('edtf-converter');
const converter = new Converter();
converter.textToEdtf('1940 until about June 1942');
// -> '1940/1942-06~'
converter.edtfToDate('1940/1942-06~');
// -> { min: moment.utc("1940-01-01T00:00:00.000+00:00"),
//      max: moment.utc("1942-09-30T23:59:59.999+00:00") }

Browser

ES6

import * as EdtfConverter from 'edtf-converter';
const converter = new EdtfConverter.Converter();
converter.textToEdtf('1940 until about June 1942');
// -> '1940/1942-06~'
converter.edtfToDate('1940/1942-06~');
// -> { min: moment.utc("1940-01-01T00:00:00.000+00:00"),
//      max: moment.utc("1942-09-30T23:59:59.999+00:00") }

<script>

Download edtf-converter.min.js separately without the rest of the package.

<script src="edtf-converter.min.js"></script>
<script>
  const converter = new edtfConverter.Converter();
  converter.textToEdtf('1940 until about June 1942');
  // -> '1940/1942-06~'
  converter.edtfToDate('1940/1942-06~');
  // -> { min: moment.utc("1940-01-01T00:00:00.000+00:00"),
  //      max: moment.utc("1942-09-30T23:59:59.999+00:00") }
</script>

Compatibility

This package implements select features of EDTF levels 0 and 1 as specified by ISO 8601-2 with some modifications, making it compatible to EDTF.js.

Level 0

Date

Input (example) Output
12/31/2000 2000-12-31
August 4th 2000 2000-08-04
December 2000 2000-12
2000 2000

Date and Time

Not supported

Time Interval

Input (example) Output
1984 to 2001 1984/2001
February 2010 - June 2011 2010-02/2011-06
12/31/2000 to 01/08/2001 2000-12-31/2001-01-08
26-27/06/1978 1978-06-26/1978-06-27
September-October 1958 1958-09/1958-10

Level 1

Letter-prefixed Calendar Year

Not supported

Seasons

Will be supported in the future

Qualification of a Date (Uncertain/Approximate)

Input (example) Output
possibly 1984 1984?
around June 2004 2004-06~
possibly about 31/12/2004 2004-31-12%

Unspecified Digits

Will be supported in the future

Extended Interval (L1)

Only supporting open end and open start time intervals as well as approximate/uncertain modifiers

Input (example) Output
since 1970 [1970..]
until 1970 [..1970]
1950 until around June 1970 1950/1970-06~

Negative Calendar Year

Not supported