@engr-lukman/array-object-validator v1.0.0

Array Object Validator

A lightweight, TypeScript-compatible utility for checking if a value is a valid array containing only object elements.

Installation

npm install @engr-lukman/array-object-validator
# or
yarn add @engr-lukman/array-object-validator
# or
pnpm add @engr-lukman/array-object-validator

Demo

Check out the interactive Storybook demo to see the component in action.

Features

• Accurately validates arrays containing only object elements
• Distinguishes arrays from other data types
• Ensures all array items are objects (not null or primitive types)
• Full TypeScript support with type definitions
• Zero dependencies
• ES6 module compatible
• TypeScript type guards for improved type inference
• Built for Node.js 20 LTS or higher and modern browsers

Usage

Basic Usage

// ES Modules / TypeScript
import isValidArrayOfObject from '@engr-lukman/array-object-validator';

// CommonJS
const isValidArrayOfObject = require('@engr-lukman/array-object-validator').default;

// Examples
isValidArrayOfObject([]);                       // true (empty array is valid)
isValidArrayOfObject([{}, {name: 'John'}]);     // true
isValidArrayOfObject(null);                     // false
isValidArrayOfObject({});                       // false (not an array)
isValidArrayOfObject([1, 2, 3]);               // false (contains non-objects)
isValidArrayOfObject(['string']);               // false (contains non-objects)
isValidArrayOfObject([{}, 'string']);          // false (mixed content)

With TypeScript Type Guards

import isValidArrayOfObject from '@engr-lukman/array-object-validator';

function processArrayData(data: unknown): void {
  if (isValidArrayOfObject(data)) {
    // TypeScript knows data is an array of objects here
    console.log('Valid array with', data.length, 'objects');
    
    // Process each object in the array
    data.forEach(item => {
      console.log('Object keys:', Object.keys(item));
    });
  } else {
    console.log('Not a valid array of objects');
  }
}

// Type safety example
const dataFromAPI: unknown = [{ userId: 1, name: 'John' }, { userId: 2, name: 'Jane' }];

if (isValidArrayOfObject(dataFromAPI)) {
  // TypeScript correctly narrows the type
  const firstItem = dataFromAPI[0];
  console.log(Object.keys(firstItem)); // ['userId', 'name']
}

API Reference

isValidArrayOfObject(data: unknown): boolean

Checks if a value is a valid array containing only object elements.

Returns: A boolean indicating if the value is a valid array of objects.

Compatibility

• Node.js 20 LTS or higher
• Modern browsers supporting ES6 modules
• TypeScript 4.0+

Use Cases

• Validating API responses that should be arrays of objects
• Type-safe handling of unknown data structures
• Defensive programming patterns
• Data validation before processing

License

MIT © Mohammad Lukman Hussain