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For Yarn 2+ docs and migration guide, see yarnpkg.com.

Package detail

js-subtype

nandovejer15MIT1.1.0

A function to detect the type and subtype of a given JavaScript value.

type, subtype, JavaScript, type-detection, utility

readme

js-subtype

npm version
License: MIT

js-subtype is a lightweight library that allows you to determine JavaScript subtypes, making it easy to identify the exact type of an object (like Array, Date, etc.).

Features

  • Supports multiple subtypes (Array, Date, Map, RegExp, etc.).
  • Lightweight and easy to use.
  • Zero dependencies.
  • Works in both Node.js and modern browsers.

Installation

Install using npm:

npm install js-subtype

Or with yarn:

yarn add js-subtype

Usage

Here’s a quick example of how to use js-subtype:

const { getType } = require("js-subtype");

console.log(getType([1, 2, 3])); // Output: "Array"
console.log(getType(new Date())); // Output: "Date"
console.log(getType(/regex/)); // Output: "RegExp"

API

getType(value)

Returns a string representing the subtype of the given value.

  • Parameters:
    • value: Any JavaScript value.
  • Returns: The string subtype (Array, Date, Map, etc.).

Use Cases

Advanced Type Validation

Use js-subtype to validate inputs or types precisely in your applications:

function validateInput(input) {
  if (getType(input) !== "Array") {
    throw new Error("Input must be an array.");
  }
  // Additional logic...
}

Identifying Native JavaScript Objects

Determine the exact native type of an object, such as Map or Set:

console.log(getType(new Map())); // Output: "Map"
console.log(getType(new Set())); // Output: "Set"

Contribution

We welcome contributions! Please submit a pull request or open an issue if you encounter any problems. Make sure to follow the guidelines outlined in the Code of Conduct.

License

This project is licensed under the MIT License.