isPlainObject

lang

Checks if value is a plain object.

Installation

Import

import { isPlainObject } from '@tulx/utils';

Source Code

Implementation

/**
 * Checks if value is a plain object.
 *
 * @param value - The value to check.
 * @returns Returns true if value is a plain object, else false.
 *
 * @example
 * ```ts
 * function Foo() {
 *   this.a = 1;
 * }
 * isPlainObject(new Foo); // false
 * isPlainObject({ 'x': 0, 'y': 0 }); // true
 * isPlainObject([1, 2, 3]); // false
 * isPlainObject(Object.create(null)); // true
 * ```
 */
export function isPlainObject(
  value: unknown
): value is Record<string, unknown> {
  if (value === null || typeof value !== 'object') {
    return false;
  }

  if (Object.getPrototypeOf(value) === null) {
    return true;
  }

  let proto = value;
  while (Object.getPrototypeOf(proto) !== null) {
    proto = Object.getPrototypeOf(proto);
  }

  return Object.getPrototypeOf(value) === proto;
}

Example

import { isPlainObject } from '@tulx/utils';

function Foo() {
this.a = 1;
}
isPlainObject(new Foo); // false
isPlainObject({ 'x': 0, 'y': 0 }); // true
isPlainObject([1, 2, 3]); // false
isPlainObject(Object.create(null)); // true

Related Functions

castArray

Casts value as an array if it's not one.

clone

Creates a shallow clone of value.

cloneDeep

This method is like clone except that it recursively clones value.

cloneDeepWith

This method is like cloneDeep except that it accepts customizer which is invoked to produce the cloned value.

cloneWith

This method is like clone except that it accepts customizer which is invoked to produce the cloned value.

conformsTo

Checks if object conforms to source by invoking the predicate properties of source with the corresponding property values of object.