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kotlinlang

I might be wrong, but that’s what `current` means in English (and in Russian), isn’t it? 

Example:

```
userId.current().flatMap { authService.signOut(it) }.subscribe()
```

Things like `take(1)` or relying to `replay(1)` can lead to signing out user that’ll sign in later in case if `userId` had no values at the time of subscription.

Maybe `latest()` would be a better name since it relies on `withLatestFrom()`, but I’m not sure.