Why not import.meta?.env?.DEBUG?

This is a rising standard, iirc

Sounds reasonable. Created a PR for that: #175

Is this declaration preventing anyone from debugging their code with signals? If not, I'd prefer to leave things as they are now, to facilitate later re-upstreaming into Angular. Maybe we can work out a better solution with them.

I'm not so sure about that query--sounds like it'll always be false in browsers!

Is this declaration preventing anyone from debugging their code with signals? If not, I'd prefer to leave things as they are now, to facilitate later re-upstreaming into Angular. Maybe we can work out a better solution with them.

No, it's not preventing from debugging, it's just that:

1. It's an undocumented prerequisite for being able to get meaningful error messages in 2 locations in the code of the polyfill
2. The name of the variable is clearly Angular-specific. That variable is used throughout the Angular codebase for enabling additional runtime checks and errors. People using the polyfill outside of Angular might be confused by depending on this variable

At the end of the day, though, if you're planning to postpone any updates to the polyfill code or its documentation until some time later for whatever reason, it's totally fine.

Can we get angular to support import.meta.env.DEV?

Yeah let's discuss this with Angular upstream to see what we can do next.