separateArray

separateArray<T, M, N>(arr, matchFn): Object

引数arrのうち、引数matchFnの実行結果についてTrue/Falseで分けたものを返却

Example

// --- [例1] プリミティブ値を格納する配列に対して、null/undefinedであるか否かで分ける --- //
type ItemType = number | string | null | undefined
const { matches, notMatches } = separateArray<ItemType, Exclude<ItemType, Nullish>, Nullish>(
  [1, 2, 3, '4', null, undefined],
  isNotNullish
)
// matches => [1, 2, 3, '4']
// notMatches => [null, undefined]

// --- [例2] 任意のオブジェクトを格納する配列に対して、updatedAtの有無で分ける --- //
type Post = {
  title: string
  body: string
  revision?: number
  createdAt: Date
  updatedAt?: Date
}
const arr: Array<Post> = [
  { title: 'sample', body: 'sample', createdAt: new Date() },
  { title: 'sample', body: 'sample', revision: 1, createdAt: new Date(), updatedAt: new Date() },
  { title: 'sample', body: 'sample', revision: 2, createdAt: new Date(), updatedAt: new Date() },
]
const { matches, notMatches } = separateArray(arr, (post) => !post.updatedAt)
// matches => [{ title: 'sample', body: 'sample', createdAt: new Date() }]
// notMatches => [
//   { title: 'sample', body: 'sample', revision: 1, createdAt: new Date(), updatedAt: new Date() },
//   { title: 'sample', body: 'sample', revision: 2, createdAt: new Date(), updatedAt: new Date() },
// ]

Type

Name
T
M
N

Parameters

Name	Type
arr	T[]
matchFn	(v: T) => boolean

Returns

Object

Name	Type
matches	M[]
notMatches	N[]