Op provides a type of nullable values in TypeScript, which doesn't have one (yet).

It is not a new type; it just defines type Op<A> = A | NullType where NullType has no values.

Since all TypeScript types are nullable by default, any nullable value can be assigned to an Op.

But since Op is its own type, you can't accidentally assign an Op<A> to an A.

Use this along with a coding style where every nullable value is wrapped in Op, and you have null safety.

This package also provides functions for dealing with nullable values, so it will continue to be useful in the future.

Use

Op only works in typescript 1.8.0+!

Install:

npm install --save esast/op
# or:
bower install --save esast/op

In your code:

import Op, {orDefault} from 'op/Op'

// Wrap nullable types in `Op`.
const opNum: Op<number> = null
// Use helper functions to get null-safe values.
const num: number = orDefault(opNum, () => 0)

The package should work in both CommonJS and AMD environments.

Documentation

HTML documentation coming soon! For now, see Op.ts.

Contribute

Please make an issue if there's anything you'd like added or changed.