is-reference

Determine if a value is an instance of a primitive reference type.

A value is a reference if it is an instance of a primitive reference type, such as String, Number, and Boolean.

Usage

    npm install @primitive/is-reference --save   # Install package via NPM
    yarn add @primitive/is-reference             # Install package via Yarn

    import { expect } from "chai";
    import isReference from "@primitive/is-reference";

    expect(isReference(new Boolean(true))).to.be.false;
    expect(isReference(new String("boo"))).to.be.false;
    expect(isReference(new Number(42))).to.be.false;

    expect(isReference(isReference)).to.be.false;
    expect(isReference(undefined)).to.be.false;
    expect(isReference(null)).to.be.false;
    expect(isReference("boo")).to.be.false;
    expect(isReference(true)).to.be.false;
    expect(isReference(42)).to.be.false;
    expect(isReference(new Symbol("boo"))).to.be.false;
    expect(isReference({ foo: "bar" })).to.be.false;

This package contains TypeScript type declarations. Furthermore, the package uses TypeScript type guards to allow type inference to influence intellisense.

    if (isReference(x)) {
        // IntelliSense now knows `x` is a reference value.
        let y: Reference = x;
    }

Content Delivery Network (CDN)

This package can be imported via unpkg as demonstrated below.

    <script src="https://unpkg.com/@primitive/is-reference/dist/index.min.js">
    <script type="application/javascript">
        var x = new Number(42);
        if (isReference(x)) {
            // `x` is of a reference type!
        }
    </script>

Build & Test

This package uses Gulp for building, and Chai and Mocha for testing.

    npm install     # Installs dependencies.
    npm run build   # Build the project.
    npm test        # Run tests.

License

Refer to the LICENSE file for license information.