is-prime-value

Small utility to check whether a value is a prime number. Returns true for prime integers, false otherwise.

This package now ships TypeScript sources (src/) and builds to lib/ during publishing or when running the included prepare script.

Installation

From npm (recommended):

npm install is-prime-value

If you install directly from this Git repository, build artifacts are not committed — run the build step locally after installing:

npm install
npm run build

When publishing, the prepare script will run automatically to generate lib/ and type declarations.

Usage (JavaScript)

const isPrime = require("is-prime-value");

console.log(isPrime(47)); // true
console.log(isPrime(1)); // false
console.log(isPrime(100)); // false
console.log(isPrime("2")); // true (numeric string accepted)

Usage (TypeScript)

Type definitions are provided. Example:

import isPrime = require("is-prime-value");

isPrime(7); // true

// or with esModuleInterop enabled
// import isPrime from 'is-prime-value';

Behavior & validation

• Accepts numbers and numeric strings (uses is-number internally).
• Throws TypeError for non-numeric values.
• Throws Error for non-integer numeric values.
• Throws RangeError for values outside Number.MAX_SAFE_INTEGER.
• Negative numbers are treated by absolute value (e.g., -3 is prime).

Algorithm: trial division up to sqrt(n) with even-number short-circuiting (O(sqrt(n))).

Development

Build and test locally:

npm install
npm run build
npm test

Notes

• The repository keeps TypeScript sources in src/. The lib/ directory is a build artifact and is ignored by .gitignore.
• The package includes a prepare script so npm publish and installs from git will build before publish.

License

ISC