[dancer-users] [Dancer-dev] dancer_major_version

[David Precious]

On Thu, 27 Dec 2012 12:46:20 +0100
Alexis Sukrieh <sukria at sukria.net> wrote:

> Actually, the whole thing is that dancer_version (or major_version)
> should clearly not be used for plugins to check their compatibility
> with the core. Actually, what plugin should do is to use api_version.
> 
> Simple example :
> 
> Dancer 1.9999_01 is "Dancer 1" is you look at the VERSION (whatever
> method you choose) but it's actually "Dancer 2" regarding its core.
> 
> So to summarize:
> 
>   - dancer_major_version should be removed, it has been added in a
> rush, while releasing 1.9999_01 but was a mistake because of the
> reason explained above
>   - api_version should be used whenever something needs to check its
> compatibility with the core

I'm not sure; a lot of existing plugins use dancer_version, and it's
meaning is fairly clear.

I think the pragmatic approach is to let them continue to do so, with a
couple of tweaks:

 - dancer_version can strip /_\d+$/ so that dev releases don't cause
   issues
 - a special-case for D2 - e.g. return 2 if ($version >= 1.9) - if the
   code is calling dancer_version, it most likely wants to know the
   difference between D1 and D2, I can't see that it's likely to be
   used in many other ways, you'd tend to use $Dancer::VERSION for that.

If that's no good, a potential other solution, which may be a little
voodish, is to return an object which uses overload to overload
stringification and comparison, so if you use it as a string (if you
wanted to output the current Dancer version) it gives you the full
version (perhaps minus the _\d+$ from a dev release), but if you use it
in a comparison (e.g. if (dancer_version >= 2), it Does The Right
Thing).

What do you think?

Whatever we decide to do, if we do change the behaviour of
dancer_version a little it should be documented clearly.



-- 
David Precious ("bigpresh") <davidp at preshweb.co.uk>
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