TS-Polyfill

> Runtime polyfills for TypeScript libs, powered by core-js! :battery: :nut_and_bolt:

 

Install

npm install ts-polyfill

Getting Started

- Modify your project tsconfig.json to add type definitions required.

- (Obviously, you don't need EVERYTHING. Pick the ones you actually need to minimize bandwidth!)

- In this example, we are targeting ES2015 so only ES2016 and above polyfills are needed:

``json
{
"compilerOptions": {
"target": "ES2015",
"lib": [
"DOM",
"DOM.Iterable",
"ES2015",
"ES2016.Array.Include",
"ES2017.Object",
"ES2017.String",
"ES2018.AsyncIterable",
"ES2018.Promise",
"ES2019.Array",
"ES2019.Object",
"ES2019.String",
"ES2019.Symbol",
"ES2020.Promise",
"ES2020.String",
"ES2020.Symbol.WellKnown"
]
}
}
`

> It is 2020 and you should be targeting ES2015. Internet Explorer 11 and Windows 7 are no longer supported by Microsoft and no longer receive security patches.

- Then, in the entry point of your application, import the polyfills.

- The complete list of available polyfills (including ES2015 polyfills for poor souls targeting ES5) can be found here: https://github.com/ryanelian/ts-polyfill/tree/master/lib

`ts
// index.ts
import 'ts-polyfill/lib/es2016-array-include';
import 'ts-polyfill/lib/es2017-object';
import 'ts-polyfill/lib/es2017-string';
import 'ts-polyfill/lib/es2018-async-iterable'; // for-await-of
import 'ts-polyfill/lib/es2018-promise';
import 'ts-polyfill/lib/es2019-array';
import 'ts-polyfill/lib/es2019-object';
import 'ts-polyfill/lib/es2019-string';
import 'ts-polyfill/lib/es2019-symbol';
import 'ts-polyfill/lib/es2020-promise';
import 'ts-polyfill/lib/es2020-string';
import 'ts-polyfill/lib/es2020-symbol-wellknown';

import 'ts-polyfill/lib/es2020-global-this'; // globalThis (no tsconfig.json lib)
`

> Shameless self-promotion: use instapack for easy, rapid, and painless web app development using TypeScript!

Alternative Techniques

- Include everything implicitly: :ok_hand:

- EXCEPT these non-essential polyfills (for portability): es2015-iterable, es2015-reflect, es2015-symbol, es2015-symbol-wellknown, es2017-typed-arrays, es2018-async-iterable, es2019-symbol, es2020-symbol-wellknown

`ts
import 'ts-polyfill';
`

- Include everything (also with exceptions listed above) using a pre-built script: download then include these as