types

👉 DistributiveOmit

Same as Omit, but works with unions.

import { DistributiveOmit } from '@crustack/utils'

// works as expected:
// Omit<{ a: string, b: string }, "c"> | Omit<{ b: string, c: string }, "c">
type T = DistributiveOmit<
  { a: string; b: string } | { b: string; c: string },
  'c'
>

// forgets both 'a' and 'c':
// { b: string }
type U = Omit<{ a: string; b: string } | { b: string; c: string }, 'c'>

👉 EntryOf

Transform an object type into a union of its entries.

import { EntryOf } from '@crustack/utils'

type MyObject = {
  a: number
  b: string
}

type Entry = EntryOf<MyObject>
// ['a', number] | ['b', string]

👉 KeyOf

Same as keyof, but works with unions.

import { KeyOf } from '@crustack/utils'

type MyObject =
  | {
      a: number
      b: string
    }
  | {
      b: string
      c?: boolean
    }

type T = KeyOf<MyObject>
// 'a' | 'b' | 'c'

type U = keyof MyObject
// 'b'

👉 MaybeArray

Describe a type that might be an Array

import { MaybeArray } from '@crustack/utils'

type T = MaybeArray<{ a: string }>
// T = { a: string } | Array<{ a: string }>

👉 MaybePromise

Describe a type that might be a Promise

import { MaybePromise } from '@crustack/utils'

type T = MaybePromise<{ a: string }>
// T = { a: string } | Promise<{ a: string }>

👉 Prettify

👉 UnionToIntersection

Transform a Union type to an Intersection type.

import { UnionToIntersection } from '@crustack/utils'

type I = UnionToIntersection<{ a: string } | { b: number }>
// I = { a: string } & { b: number }

👉 ValueOf

Extracts the value types of an object type.

Same as KeyOf, but for values.

import { ValueOf } from '@crustack/utils'

type MyObject = {
  a: number
  b: string
}

type T = ValueOf<MyObject>
// number | string

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