Date Fns Lost

Lost tools for moment including domain specific language for time manipulations and schedule operations.

1import momentRange from 'moment-range'
2import momentTz from 'moment-timezone'
3const moment = momentRange.extendMoment(momentTz)
4import lost from 'date-fns-lost'
5const {
6  chrono,
7  spanner,
8  schedule,
9  dsl,
10  iso8601
11} = lost(moment)
12
13const content = `
14  //
15  // A date constant is either an iso8601 string or a reference
16  // to another constant. Constants can optionally be followed
17  // immediately by spanner operations.
18  //
19  // day_in_june: 2018-06-15T10:00:00Z
20  // start_of_june: day_in_june/M
21  //
22  //
23  // An interval is a repeating pattern and can be specified as:
24  //
25  // interval(anchor, duration, repeat)
26  //
27  // Where:
28  //   anchor   - A reference to a constant optionally followed
29  //              by spanner operations.
30  //   duration - A spanner operation to calculate the duration
31  //              of each iteration.
32  //   repeat   - A number followed by the name or short code
33  //              of a unit to jump forward and backwards from
34  //              anchor to create the pattern.
35  //
36  //
37  // A range is all time between a start and an end
38  //
39  // range(start, end)
40  //
41  // Where:
42  //   start    - A reference to a constant optionally followed
43  //              by spanner operations. Inclusive in the range.
44  //   end      - A reference to a constant optionally followed
45  //              by spanner operations. Inclusive in the range.
46  //
47  //
48  // Both interval and range cannot accept iso8601 parameters,
49  // these can be defined as constants and referenced.
50  //
51  //
52  // Spanner operations are executed sequentially against a
53  // constant or if not supplied will default to the current time.
54  //
55  // (timezone) - Changes all following operations to be
56  //              executed in the supplied timezone.
57  //              http://momentjs.com/timezone/
58  // +5days     - Add or substract a multiple of a time unit.
59  // +5d4h      - Can use short codes and multiple units.
60  // /M         - Jump to the start of time unit.
61  //
62
63  start: now/M
64  end: now+4M/M
65
66  result:
67  + interval(now/M, +7d, 1M)
68  * interval(/isoWeek+1d, +1d, 1w)
69
70`
71const parsed = dsl.parse(content)
72console.log(parsed.schedules)
73const clip = moment.range(parsed.constants.start, parsed.constants.end)
74const segments = schedule.between(parsed.schedules, parsed.schedules.result, clip)
75for (let segment of segments)
76  console.log(segment.start.format(iso8601), '—', segment.end.format(iso8601))