Problem with the removal of combineLatest in version 8

[scottburch]

Hello,

I have been using RxJS for pretty much all of my code for years now. I'm not new, but not a total expert either.

I read that combineLatest is scheduled to be removed in version 8. However, I use it for something that I can't find anything else to do the same job. I use it to pass in a value into xMap and return multiple results. Basically, a passthrough. I put some code below to demonstrate how I use it

The alternative to this is adding a .pipe() at the end of the newTransaction, and forming the tuple. However, I find that to be a bit messier. If someone has a better way to do this, let me know. But, if combineLatest is removed, I would need to find a way to do this without it.

Thanks

                 switchMap(keys => combineLatest([
                    of(keys), newTransaction({
                        msgs: [{path: 'my/transaction', data: {foo: 10}}]
                    })
                ])),
                switchMap(([keys, tx]) => signTx(tx, keys)),

[AronHoxha]

Hi @scottburch !
For your particular example I think you can utilize combineLatestWith, as follows:

                 // observable that resulted to keys ...
                 combineLatestWith(newTransaction({
                    msgs: [{path: 'my/transaction', data: {foo: 10}}]
                })
                switchMap(([keys, tx]) => signTx(tx, keys)),

Assuming that newTransaction() function is not dependent on the keys, nor is it supposed to be lazily evaluated

In addition AFAIK, combineLatest is not being totally removed in v8 (or I would also be very sad 😅 ), just some specific implementation of it are, for instance rest parameters implementation:

combineLatest(
  of(1),
  of(2),
  of(3),
  // ...
)

Hope this helps.

[scottburch]

@AronHoxha Thanks for the reply.

Yea, I thought that combineLatestWith would work, but it does not do the same thing for some reason. I can't remember why. But, I think I ran into the same thing after I posted, that the array argument implementation was not being removed, just the ...rest implementation. So, all should be good.

Thanks again. I really appreciate it. I can try the combineLatestWith again if I need to, or try to figure out why it did not work the same.