typed

Statically typed properties for object literals

Install

Download the CJS, ESM, UMD versions or install via NPM:

npm install @ryanmorr/typed

Usage

Restrict properties to a native data type:

import typed from '@ryanmorr/typed';

const object = typed({
    foo: String,
    bar: Number 
});

object.foo = 'foo';
object.bar = 123;

Constrain a property to a user-defined constructor:

function Foo() {}

const object = typed({
    foo: Foo
});

object.foo = new Foo();

If a value of the wrong type is assigned to a property, a TypeError will be thrown:

const object = typed({
    foo: String
});

object.foo = 123 // throws: Invalid value assignment on "foo", expected: String, actual: Number

License

This project is dedicated to the public domain as described by the Unlicense.