JavaScript

New Features in 2020

Dynamic Import

async function loadLib(){
  const lib = await import('some lib');
}

Optional Chainning

let item = data?.prop?.['something'] // no error when data is undefined

Nullish Coalescing

...
const number = value ?? 400 // assign 400 to number if value is null or undefined
...

Big Int

const largeNum = BigInt(some big number);
const superLarge = largeNumber ** 23n

CSS

Ticks

Fake Scrollspy: Code

HTML

Lazy loading

<img loading="lazy" />