Rename `of` to `just`

[benlesh]

After speaking with @kwonoj and others, we think it would be best to rename of to just.

1. It's still terse
2. There's precedent (it was just in RxJS 4 and under, and in other Rx dialects)
3. It's less confusing to read than of
4. IDEs don't color code just like they do of

Thoughts? Questions? Concerns?

The process here would be to:

1. deprecate of, but leave it
2. Add just (of would alias just)

[benlesh]

Related #3514

[claudiordgz]

Oh no of is only in the bindings of PHP! 😨

I got no preference, both of and just are short enough, just is short enough to implement and long enough to make it a little bit more readable... observableOf seems overkill, wouldn't the rest of the observable functions have to follow a similar pattern? Consistency and all that?

[alex-okrushko]

I assume there was some prior discussion to move from just to of. Do you happen to know where that is?

[kwonoj]

As attached #3514 have history around.

[alexcastillo]

I feel “just” is not very meaningful and provides no context. Is “observableOf” not an option? It is very descriptive and leaves less room for confusion.

[benlesh]

observableOf is really verbose, that's my only objection. It's unfortunate that "observable" is such a long word haha.

[mattwilson1024]

My team always aliases of to observableOf in the import, so I'm pleased to see that get suggested. It's a little more verbose, granted, but it reads nicely and makes things a lot more obvious in my opinion.

[wesleygrimes]

What about ‘oof’? Short for “observableOf”...

[leifwells]

of makes sense to me. But not all of these "action words" make sense, so I guess it doesn't need to make sense.

So, if you're going to do something, option 2 would be my preference, along with clear guidance.

[cartant]

@wesleygrimes I was going to suggest - facetiously - that o10f could be used, but oof is better!

Seriously, though, I'm fine with just.

[Meligy]

If I have to choose, I'd keep of. Because just doesn't sound good in code that's all about composition.

If we have to change of (worst problem might be IDE colouring. It's also not a very clear word, but alternatives will probably have the same problem to be short), then maybe a totally new word. I thought of with but it also comes with its own problems.

For now, just of is fine.

[alex-okrushko]

@kwonoj #3514 has the recent history (which I participated in), I was asking to the history when just was dropped in favor of of. Is that available? I'm curious what the thinking was at the time that lead to such decision.

[kwonoj]

@alex-okrushko there was no filed issue in repo around those afaik.

[benlesh]

Basically, the current of is just the implementation of the static Observable.of per the tc39 proposal.

RxJS 4 had Observable.of, return and just that all did the same thing. In version 5 we reduced it to the one that was required for the tc39 proposal.