Re: How to find when a function/var has been added

[Przemysław Wojnowski]

W dniu 09.08.2015 o 08:26, Stephen Leake pisze:
> Przemysław Wojnowski <address@hidden> writes:
> > > And it will be very
> > > easy to forget to change it on a later edit; no information is one
> > > thing, wrong information is worse.
> > I don't get this one. To change "Since: x" on later edit? Why?
>
> If the arg list or semantics of the function changes, the version in
> which that happens should be noted.
This could be noted in function's docs.

> > Clearly we disagree here.
> > IMHO it is useful to any programmer that would like to write an Emacs
> > package that works across some emacsen. For such people Emacs is a
> > programming platform that can be deployed in different versions (API
> > versions - in case of Emacs different libs/functions/vars). Having
> > "Since: x" makes it faster learn and hence to write software that
> > works on different versions of the platform.
>
> I misspoke; it would be useful information to have. But the cost of
> providing it, at least with the mechanism you propose, is too high, for
> a volunteer project like Emacs. Especially since there are other
> reasonable ways to get the same information.
All I propose is to add such information incrementally. For some libs it's very 
easy to add - for example seq.el has been added in Emacs 25, so it can be added 
right away. And not all the functions has to be documented in such way -  I 
don't expect anyone to add "Since" to, say, car function. ;-)

> > For example Jira is such a platform. It may be installed in different
> > versions, and a programmer that writes Jira plugins needs to know
> > which classes/methods/vars can be used safely for a plugin.
>
> What mechanism do they use to document this information? And how much
> money do they spend doing that?
>
> Another example is Google Android; every function has "added in API nn"
> annotation in the html docs. I have no idea how they generate that.
Another example is Clojure.
I don't thing any of them used some mechanism. AFAIK the standard way is to add 
it manually (and possibly _incrementally_ when added after releasing an API).

> But Google has lots of money to pay programmers to produce that info,
> and they have a strong compatibility goal; they want people to write
> code that can run on many different versions of the Android platform.
What goal does Emacs have? Is there any project vision?

> Emacs has neither the money, nor the strong compatibility goal (the latter
> partly because of the former, of course).
There's no direct relationship between the two. Money != compatibility.
Probably here are more great developers that most companies could afford.

> In general, the lack of this kind of detailed documentation is part of
> the cost of using open-source software developed by volunteers.
No, its just cost of attitude. Adding it incrementally costs close to nothing.

Anyways, this discussion leads nowhere, because either way nothing will happen.

PS Sorry for late reply. I've been busy. :-|

Cheers,
Przemysław