Recurrent event generator with constraints.
See about section for further informations on project purposes and how it works.
npm install slotte
# or, with yarn
yarn add slotteIn the following example we are creating recurrent events for a working week where we allow events to be created from 8am to 12am and from 2pm to 6pm. Events has length of 1 hour.
Code
import { generator } from "../generator";
import { addInterval, Interval } from "../interval";
import { changeTime, flatten, ordMoment, takeUntil } from "../util";
// recurrent event size
const interval: Interval = { amount: 1, unit: "hour" };
// start and stop of generation
const start = moment("2020-10-11 00:00");
const stop = moment("2020-10-18 00:00");
// some util functions for constraints
const changeTimeTo08 = changeTime("8:00");
const changeTimeTo12 = changeTime("12:00");
const changeTimeTo14 = changeTime("14:00");
const changeTimeTo18 = changeTime("18:00");
// constraints
const notOnSathurday = (c: Moment) => c.isoWeekday() !== 6;
const notOnSunday = (c: Moment) => c.isoWeekday() !== 7;
const notBefore8am = (c: Moment) => ge(changeTimeTo08(c))(c);
const notAtLaunch = (c: Moment) =>
!c.isBetween(changeTimeTo12(c), changeTimeTo14(c), undefined, "[)");
const notAfter18pm = (c: Moment) => lt(changeTimeTo18(c))(c);
const constraints = [
notOnSathurday,
notOnSunday,
notBefore8am,
notAfter18pm,
notAtLaunch,
];
// generator
const gen = generator(interval)(constraints)(start);
// get values from generator and log them
// Note: values are returned in reverse order
console.log(flatten(takeUntil(stop)(gen)));Result
Note: the x represents the event existence.
| Monday | Tuesday | Wednesday | Thursday | Friday | Sathurday | Sunday | |
|---|---|---|---|---|---|---|---|
| ... | |||||||
| 07:00-08:00 | |||||||
| 08:00-09:00 | x | x | x | x | x | ||
| 09:00-10:00 | x | x | x | x | x | ||
| 10:00-11:00 | x | x | x | x | x | ||
| 11:00-12:00 | x | x | x | x | x | ||
| 12:00-13:00 | |||||||
| 13:00-13:00 | |||||||
| 14:00-15:00 | x | x | x | x | x | ||
| 15:00-16:00 | x | x | x | x | x | ||
| 16:00-17:00 | x | x | x | x | x | ||
| 17:00-18:00 | x | x | x | x | x | ||
| 18:00-19:00 | |||||||
| ... |
Module generator.
Syntax
export const generator = (interval: Interval)
=> (constraints: Constraint[])
=> (start: Moment): Generator<Slot, Slot, Slot>`Semantic Return a generator that creates recurrent events (Slot) with size interval, according to constraints, starting from start.
Usage
// create the generator
const oneHourInterval = { amount: 1, unit: "hour" };
const constraints = [
// your constraints
];
const start = moment();
const myGen = generator(oneHourInterval)(constraints)(start);
// use the generator
// with .next()
myGen.next().value;
// with for .. of
for (const event of myGen) {
// use `event`
}Note This function is curried, so you can use it also by fixing the interval parameter first, then constraints and then the start date.
const oneHourGenerator = generator({ amount: 1, unit: "hour" });
const morningGenerator = oneHourGenerator([between8amAnd12am]);
const afternoonGenerator = oneHourGenerator([between14amAnd18am]);
const myGen1 = morningGenerator(moment());
const myGen2 = morningGenerator(moment("2020-10-10 17:00:00"));
const myGen3 = afternoonGenerator(moment());
const myGen4 = afternoonGenerator(moment("2020-10-10 17:00:00"));Module util.
Syntax
type SlotGenerator = Generator<Slot, Slot, Slot>;
export const take = (n: number)
=> (iterable: SlotGenerator): Slot[]Module util.
Syntax
type SlotGenerator = Generator<Slot, Slot, Slot>;
export const takeUntil = (stop: Moment)
=> (generator: SlotGenerator): Slot[]Module util.
Syntax
export const flatten = (ss: Slot[]) => Info[]Module util.
Syntax
export const changeTime: (time: string) => (current: Moment) => Moment;Semantic
Change current time to time.
There are many predefined constraints that you can use in combination with your own constraints. See file constraint.ts.
npm run test
# or, with yarn
yarn testSlotte is a constrained time slot generator, or better, a recurrent event generator with constraints. This allows you to create fixed-size, recurrent events without saying explicitly when to repeat the event.
The main goal of slotte is in fact to facilitate bulk creation of fixed-time recurrent events. As you can see from the example above, we can use constraints for saying whether to allocate an event in a given time.
- entirely written in typescript, which ensures type safety
- heavily tested: less bugs, less problems
- boosted performance with lazy generator for recurrent event sequences
- adherent to functional programming style
- date standardization with momentjs
This project is MIT licensed. See LICENSE file.