eqOrIn

Turns a list of values into a query value that matches any of them: a single remaining value becomes an equality match, everything else a $in. Values are deduplicated first, so ['a', 'a'] collapses to the equality form. An empty list yields { $in: [] }, matching nothing — check for emptiness first if your adapter dislikes an empty IN ().

Deduplication compares primitives with SameValueZero and non-primitives deep-equal, so value wrappers like Date or a mongo ObjectId collapse even though they are distinct references. Note that deep equality ignores key order, so two plain objects with the same entries in a different order count as one.

  import { eqOrIn
 } from 'feathers-utils/utils';

Example

import { eqOrIn } from 'feathers-utils/utils'

eqOrIn([1, 2, 3]) // => { $in: [1, 2, 3] }
eqOrIn([1]) // => 1
eqOrIn([1, 1]) // => 1
eqOrIn([]) // => { $in: [] }

// distinct references, equal values
eqOrIn([new Date(5), new Date(5)]) // => Date(5)

// building a query for related records
const params = { query: { userId: eqOrIn(userIds) }, paginate: false }

Type declaration

Show Type Declarations

/**
 * Turns a list of values into a query value that matches any of them: a single
 * remaining value becomes an equality match, everything else a `$in`. Values are
 * deduplicated first, so `['a', 'a']` collapses to the equality form. An empty
 * list yields `{ $in: [] }`, matching nothing — check for emptiness first if your
 * adapter dislikes an empty `IN ()`.
 *
 * Deduplication compares primitives with `SameValueZero` and non-primitives
 * deep-equal, so value wrappers like `Date` or a mongo `ObjectId` collapse even
 * though they are distinct references. Note that deep equality ignores key order,
 * so two plain objects with the same entries in a different order count as one.
 *
 * @param values the values to match against
 * @returns the single value, or a `$in` over the deduplicated values
 *
 * @example
 * ```ts
 *
 *
 * eqOrIn([1, 2, 3]) // => { $in: [1, 2, 3] }
 * eqOrIn([1]) // => 1
 * eqOrIn([1, 1]) // => 1
 * eqOrIn([]) // => { $in: [] }
 *
 * // distinct references, equal values
 * eqOrIn([new Date(5), new Date(5)]) // => Date(5)
 *
 * // building a query for related records
 * const params = { query: { userId: eqOrIn(userIds) }, paginate: false }
 * ```
 *
 * @see https://utils.feathersjs.com/utils/eq-or-in.html
 */
export declare function eqOrIn<T>(values: readonly T[]):
  | T
  | {
      $in: T[]
    }

Argument	Type	Description
values	readonly T[]

eqOrIn ​

Example ​

Type declaration ​

eqOrIn

Example

Type declaration