From: James Britt <jamesUNDERBARb@...>
Date: 2004-07-30T08:04:25+09:00
Subject: Re: Including other people's Ruby libs in your package

Jamis Buck wrote:

> James Britt wrote:
> 
>> Aredridel wrote:
>>
>>>
>>> Speaking as a packager, don't. Just document, clearly, the dependencies
>>> and where to get them.
>>> It's annoying to have to patch away the extra cruft when packaging a
>>> package for distribution with a linux distro -- but that's the job --
>>> make it as light as possible with all the features.
>>
>>
>>
>> I've considered this, but find it potentially too annoying to the user.
>>
>> I would prefer that people be able to just download a tarball, extract 
>> it, and copy over a directory to the libs dir.  And it just works.
> 
> 
> On the other hand, it can be very annoying for a user as well when they 
> already have a *newer* version of that same dependency installed, and 
> then they install your library and suddenly things break.

That's right.  So let's don't do that. :)

That question is, What's the best way?

One approach is change $: to look in some specified directory, as a last 
resort, if the standard path does not turn up the needed lib.

So, for example, if BlueCLoth is already installed, then the 
pre-packaged copy is never loaded because a "correctly" installed 
version has been found.

If my lib is installed in /foo/bar and my class file does
    $:.push "/foo/bar/dependencies"  # or something along those lines
then my special directory should be the last place Ruby looks for a 
file.  Or no?

> 
> If nothing else, provide two versions of your package: one *with* 
> dependencies, and one without. I'm in the camp that prefers applications 
> NOT be shipped with their dependencies included, but I can understand 
> that others may prefer the other way.
> 
> The moral of the story is that there isn't a perfect solution to this, 
> unfortunately. :( Rubygems' dependency feature comes close, though.
> 

For Gems, it might be nice (or feature-creep overkill) to specify that, 
if a user refuses to install dependency Foo, then fail the installation, 
but if they refuse pseudo-dependency Bar, that's OK, keep going with a 
"You're going to miss some good stuff" warning.