[discussion] clean imports to replace `rxjs/add/observable/xyz`

[jeysal]

Now that lettable operators are coming (#2667) to get rid of the import 'rxjs/add/operator/xyz' mess, the static Observable methods for creation (of, timer, ...) and composition (merge, zip, ...) will probably need the same treatment to get rid of import 'rxjs/add/observable/xyz'.

I didn't find any issue or PR for this (probably not in scope of #2667, judging by the title and current commits), but I'm sure @benlesh has some ideas already?

It already seems to be possible to import these static methods properly using import { merge } from 'rxjs/observable/merge' etc, although this is not documented in the installation section of the docs.
However, if I didn't miss anything this approach seems quite clunky because

1. each method requires a separate import statement
2. the imports are not available on one central object like they are on Observable when using the add/observable imports
3. resulting from 2, they may need to be aliased because e.g. merge is a very generic name that does not convey correlation with RxJS

My personal comments on this:
1 could be resolved by centralizing the exports of the static methods similar to the rxjs/operators from #2667
2 does not appear to have an obvious solution, unfortunately there is no import { merge, zip } as ObservableFactoryThingy unless you're importing everything (*)
3 is probably not a large problem, especially since the same thing will apply for lettable operators (map, min etc). I certainly don't think it justifies exporting them as observableOf, mergeObservables etc instead. Either way, a possible solution to 2 might resolve 3 as well.

[jeysal]

@benlesh do you have some thoughts about the static methods already?

[jeysal]

Closing due to apparent lack of relevance.
If anybody is interested in this, feel free to comment / reopen.

[kenjiqq]

After upgrading to the newest rxjs with angular 5 now i was actually looking for exactly the same thing. How to get rid of the import 'rxjs/add/observable/xyz'. Assuming from this issue that this is still the way to do it for static methods

[OliverJAsh]

This PR seems to have quite a bit of interest judging from the votes on the original post. I think the points are still valid as well. Could we re-open this issue?

I have just migrated to lettable operators, but I'm still using the old method of "import patching" for static creation/composition methods like fromEvent. (Confusingly, some methods are available without specifying imports, like of. I'm not sure if this is intended or documented anywhere? Or am I mistaken?)

I occasionally run into bugs whereby I've forgotten to import a static method. Thus, I would like to switch to using real dependencies, however I am hesitant because of the issues mentioned by @jeysal. Primarily this is because of 3 (ambiguous naming like merge requires aliasing).

[jeysal]

It seems like #3145 will mostly resolve those problems with v6.

[benlesh]

FWIW: There has always been the ability to import these directly via:

import { of } from 'rxjs/observable/of';
import { fromEvent } from 'rxjs/observable/fromEvent';
import { timer } from 'rxjs/observable/timer';

The only noteworthy exceptions are throw and if, which are exported with underscores because of keyword collisions:

import { _if } from 'rxjs/observable/if';
import [ _throw } from 'rxjs/observable/throw';

[jeysal]

Yeah I mentioned that in the issue description, but 1. was rather about the central import path for all creation methods, which is introduced only as of #3145. But maybe @kenborge didn't see that so thanks for pointing it out again 👍

[kenjiqq]

I did actually miss that part so thanks

[jeysal]

I'll go ahead and close this again because I think #3145 will make everyone happy.

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.