Function hasKeys

Checks if an object has all of the provided own properties.

Example

Basic Usage

hasKeys({ a: 1, b: 2, c: 3 }, ['a', 'b']) // true
hasKeys({ foo: 1, bar: 2 }, ['buzz']) // false
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Type narrowing

const obj: { a: string; b: string } | { c: number; d: number }

if (hasKeys(obj, ['a'])) {
  obj // type: { a: string; b: string; }
  obj.c // error
} else {
  obj // type: { c: number; d: number; }
  obj.a // error
}
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Paired with assert

import { assert } from 'uft'

const obj: { a: string; b: string } | { c: number; d: number }
assert(hasKeys(obj, ['d']), 'expected object to have key "d"')
obj // type: { c: number; d: number }
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