Superutils

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Function: isObj() ​

isObj<T>(x, strict): x is T

Defined in: packages/core/src/is/isObj.ts:44

Check if value is an object.

Type Parameters ​

T ​

T = Record<PropertyKey, unknown>

Parameters ​

x ​

unknown

value to check

strict ​

boolean = true

(optional) whether to exclude anything other than plain object. Eg: Array, Map, RegExp, Set etc.

Default: true

Valid objects:

  • object literals (Prototype: Object.prototype)
  • objects created using Object.create(null)

Valid when strict mode off (false):

  • all of above
  • buit-in objects like Date, Error, Map, Set, Uint8Array etc
  • custom Class instances
  • objects created using Object.create(object)

Always invalid:

  • null, undefined, NaN, Infinity
  • primitive: String, Number, BigInt...

Returns ​

x is T

Example ​

typescript
import { isObj } from '@superutils/core'

console.log(isObj(null)) // false
console.log(isObj(undefined)) // false
console.log(isObj(NaN)) // false
console.log(isObj(Infinity)) // false
console.log(isObj({})) // true
console.log(isObj({ a: 1, b: 2})) // true
console.log(isObj(Object.create(null))) // true
console.log(isObj(new Map())) // false (strict)
console.log(isObj(new Map(), false)) // true (non-strict)
console.log(isObj(new Error('error'))) // false (strict)
console.log(isObj(new Error('error'), false)) // true (non-strict)
class Test { a = 1 }) // a custom class
console.log(isObj(new Test())) // false
console.log(isObj(new Test(), false)) // true