This JavaScript feature adds the capability for testing the existence of a private field in an object: "#foo in obj" Proposal: https://github.com/tc39/proposal-private-fields-in-in The feature has reached Stage 3 in TC39.

Motivation

See proposal https://github.com/tc39/proposal-private-fields-in-in for motivating examples.

Specification

Editor's draft

Status in Chromium

Blink>JavaScript>Language


In developer trial (Behind a flag) in:

  • Chrome for desktop release 90
  • Chrome for Android release 90
  • Chrome for iOS release 90

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.

  • No signal
  • No signal
  • No signal
  • No signals

Owners

Last updated on 2021-02-22