Null coalescing operator in React JS/ Typescript

javascript .net reactjs typescript null-check
Praveen Kumar picture Praveen Kumar · Apr 17, 2018 · Viewed 9.2k times · Source

We have the Null coalescing operator in .NET and we can use as below

string postal_code = address?.postal_code;

Same thing can we do in React JS?

What i found like we can do with && operator

in address.ts file

string postal_code = address && address.postal_code;

what i need like .net feature is possible in typescript with react JS, is that possible ?

something like:

string postal_code = address?.postal_code // I am getting the error in this line if I try to use like .NET

Answer

Fenton picture Fenton · Apr 17, 2018

This is a proposed feature in TypeScript, under the legendary Issue #16

It won't be introduced into TypeScript until the ECMAScript spec for this feature is firm as there is a desire for the TypeScript implementation to follow that specification - so you'll get it early, but not massively early in this case.

It is referred to as any of the following:

  • Null Propagation Operator
  • Existential Operator
  • Null Coalesce Operator

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