microsoft/TypeScript (original) (raw)
Suggestion
https://github.com/tc39/proposal-private-fields-in-in is stage 3 now.
🔍 Search Terms
esnext. private field. class
List of keywords you searched for before creating this issue. Write them down here so that others can find this suggestion more easily and help provide feedback.
✅ Viability Checklist
My suggestion meets these guidelines:
- This wouldn't be a breaking change in existing TypeScript/JavaScript code
- This wouldn't change the runtime behavior of existing JavaScript code
- This could be implemented without emitting different JS based on the types of the expressions
- This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
- This feature would agree with the rest of TypeScript's Design Goals.
⭐ Suggestion
📃 Motivating Example
class C { #brand = 42;
static isC(obj: C) { return #brand in obj; // should work } }