Re: [Caml-list] OPAM conventions

[Wojciech Meyer <wojciech.meyer@gmail.com>]

On Wed, Dec 12, 2012 at 5:36 PM, Anil Madhavapeddy <anil@recoil.org> wrote:
> On 12 Dec 2012, at 14:47, Dario Teixeira <darioteixeira@yahoo.com> wrote:
>>    Good arguments can be made for and against each option.  Though this
>>    is largely a bike-shedding issue, I think the community should make
>>    a decision sooner rather than later.
>
> I generally don't like typing too much, and so prefer the shorter name.
> But converting packages names isn't really a big deal and can be done
> mechanically, so it's more important to build up the database first.

Indeed, but then dependent packages needs to be up-dated too!
We could have also virtual packages that could serve as a basis for
aliases when there is a strong reason to be compatible.
The good thing is that OPAM package definitions are detached from the
tarballs itself, so it's easy to up-date in a centralised way.

>> 3) Package removal
>>
>>    For most values of "foo", package "foo" will just declare ["ocamlfind"
>>    "remove" "foo"].  However, this approach seems a bit brittle to me.
>>    If the Makefile supports "uninstall" (which is the usually the case
>>    for OASIS packages), then I reckon that ["%{make}%" "uninstall"]
>>    should be preferred.
>>
>>    Having said that, it seems that ["%{make}%" "uninstall"] is currently
>>    not working (OPAM tries to download the package de novo upon removal!).
>>    Is this a bug or a feature?
>
> The issue with removal is that the package needs to be available to run
> make uninstall, hence the download.

Hmm, wouldn't be just better for OPAM to track the diff of the
repository, then just remove the files?
Possibly, having an open door for unnistall would be good for packages
like Ocsigen which might want to remove the configuration from the
system or shutdown the server.

>
> In the longer term, we've discussed letting the OPAM package declare
> which ocamlfind packages it installs, and having those automatically
> handled (i.e. the install phase asserts that the package exists as a
> post-condition, and the uninstall removes it and checks it's gone).
>
> But that's all post-OPAM-1.0! Basics first.
>
>> 4) Findlib dependency
>>
>>    Most packages do declare a dependency on ocamlfind.  However, this is
>>    not universal, even for packages that do register themselves with findlib.
>>    What should be the standard here: always declare a dependency, or omit
>>    it altogether since it is implied?
>
> If something uses ocamlfind and doesn't declare it explicitly, it's a bug.
> The continuous build system catches most of these, and in practise it doesn't
> matter as a dependent package will pull it in, but it's best to be explicit
> about it.

+1.

I'm also always convinced that ocamlfind should be taken into account
as an integral part of the system.

-Wojciech