Re: A side note on depricated components vs packagage possibilties (debian)

[Benoît Minisini <benoit.minisini@xxxxxxxxxxxxxxxx>]

Le 03/12/2024 à 22:25, gbWilly a écrit :
> We see that for example gb.report has been replaced by gb.report2
> And you would like to encourage people using the newer one.
>
> Soon, we will see that gb.db2 becomes the norm as gambas3-ide needs it.
> So, gb.db should slowly be discouraged or maybe it can even be replaced.
>
> All that depends on code compatibility.
> If I for example use gb.db in my projects and a simple change to gb.db2 
> would not cause trouble and it would be 100% code compatible with my 
> existing code. Then it could easily be replaced, without breaking 
> packages made in the past depending in the old gb.db (or gb.report and 
> so on).
>
> So the question is, are there components that can replace existing 
> onces, without breaking older code?
>
> As an example how to do in a debian recipe I will take gb.db (but it 
> could be gb.report as well):
>
> Package: gambas3-gb-db
> Architecture: any
> Section: oldlibs
> Priority: optional
> Depends: gambas3-gb-db2,
>           ${misc:Depends}
> Description: transitional package
>   This is a dummy transitional package. It can safely be removed.
>
> Package: gambas3-gb-db2
> Architecture: any
> Section: libdevel
> Depends: ${misc:Depends},
>           gambas3-runtime (>= ${binary:Version})
> Breaks: gambas3-gb-db (<< 3.20.0)
> Replaces: gambas3-gb-db
> Description: Gambas database access common libraries
>   Gambas is a free development environment based on a Basic interpreter
>   with object extensions, like Visual Basic(tm) (but it is NOT a clone!).
>   .
>   This package provides the needed common libraries for data access.
>
> If an application is packaged depending on gambas3-gb-db, it will 
> install gambas3-gb-db2.
> 2 important questions need a positive answer for that:
>
>  1. Does gambas know how to deal with that change?
>  2. Are new components code compatible with code once written using the
>     old component?
>     In short can you just switch the component for the new one, in an
>     opened project in IDE,  and then still run the project like before,
>     without any code change?
>
> I do not know all the ins and outs of how gambas deals with stuff like that.
> The packaging possibilities are there. just saying
> And I bet other distro's can do that kind of magic as well.
>
> gbWilly
>
> Gambas3 for Debian <https://gitlab.com/gbWilly/gambas3-debian-repository>
>
> Sent with Proton Mail <https://proton.me/mail/home> secure email.

Even if, for example, 'gb.db2' has the same API (at the moment) as 
'gb.db', the replacement of 'gb.db' by 'gb.db2' in a program is entirely 
up to the program's author.

Automatic replacement is too dangerous, because it can break a program 
outside of the author's responsability if there is a compatibility bug 
in the new component.

If the author want to switch to the new component, it will have to make 
a new version and a new package of its program.

So no automatic replacement, thanks!

Regards,

--
Benoît Minisini.