series

​

Basic usage

Sometimes you have an enum or union type, possibly a status, that has inherint order and you need to work with values as though they’re ordered. The series function takes many values and returns an object that let’s you do ordered logic on those values.

import { series } from 'radash'

type Weekday = 'monday' | 'tuesday' | 'wednesday' | 'thursday' | 'friday'

const weekdays = series<Weekday>([
  'monday',
  'tuesday',
  'wednesday',
  'thursday',
  'friday'
])

weekdays.min('tuesday', 'thursday') // => 'tuesday'
weekdays.max('wednesday', 'monday') // => 'wednesday'
weekdays.next('wednesday') // => 'thursday'
weekdays.previous('tuesday') // => 'monday'
weekdays.first() // => 'monday'
weekdays.last() // => 'friday'
weekdays.next('friday') // => null
weekdays.next('friday', weekdays.first()) // => 'monday'
weekdays.spin('monday', 3) // => 'thursday'

​

Complex Data Types

When working with objects you’ll want to provide a second argument to series, a function that converts non-primitive values into an identity that can be checked for equality.

import { series } from 'radash'

type Weekday = {
  day: 'monday' | 'tuesday' | 'wednesday' | 'thursday' | 'friday'
}

const weekdays = series<Weekday>(
  [
    { day: 'monday' },
    { day: 'tuesday' },
    { day: 'wednesday' },
    { day: 'thursday' },
    { day: 'friday' }
  ],
  w => w.day
)

weekdays.next({ day: 'wednesday' }) // => { day: 'thursday' }
weekdays.previous({ day: 'tuesday' }) // => { day: 'monday' }