[opam-devel] How to manage a package manager (Was: Re: [opam] Build clarification (#1149))

[Roberto Di Cosmo]

On Fri, Jan 31, 2014 at 07:54:20PM +0000, Anil Madhavapeddy wrote:
> On 31 Jan 2014, at 17:28, Roberto Di Cosmo <roberto at dicosmo.org> wrote:
> 
> >     I am a bit unhappy with the current state of affairs, where new
> >     versions of opam appear with incompatible changes in the repository format,
> >     hence different versions of the repositories: people using old versions
> >     of opam get lost in a limbo-like repository with non updated packages
> >     until they realise they need to recompile a new version of opam
> >     to see the light again.
> 
> To be clear, the reason for OPAM 1.0 to 1.1 being incompatible was "unplanned".  The original release was too strict with it's parsing, and OPAM 1.1 is now far more lax.
> 

Sure Anil, nobody is implying here that this was deliberately planned :-)
Simply, this kind of things just happen, and especially so when a piece
of software is under heavy development.

That's why one needs a clear, and simple, mechanism to ensure a smooth
transition when incompatibilities arrive (and there will be more, and
unexpected ones, you can bet on it). 

The one I outlined has no pretense of originality, it's just good practice.

-- 
Roberto