[Haskell-cafe] Hackage on Linux

[Andrew Coppin]

Ivan Lazar Miljenovic wrote:
> Hackage has limited support for distro maintainers to state which
> packages are available on the distribution.  Last I checked, it required
> distro maintainers to keep a text file somewhere up to date.
>
> Note that not all distributions bother.

Yeah, I figured. I don't see any Debian or OpenSUSE anywhere, and I know 
they do have at least a few pre-built binary packages out there.

It looks as if it's automated for Arch, however. Either that or somebody 
is spending an absurd amount of time keeping it manually up to date.

> (in particular none of us
> involved with packaging Haskell packages for Gentoo can be bothered;
> we're slowly cutting back into only keeping packages that will actually
> be used rather than all and sundry)

Well, I guess you either manually select which packages to convert, or 
you have an automated system convert everything in sight.

This whole observation came about because I noticed that some (but not 
all) of my own packages have ended up on Arch, despite being of almost 
no use to anybody. I was just curious as to how that happened.

> As for why using your distro package manager for Haskell packages is
> preferable:
> http://ivanmiljenovic.wordpress.com/2010/03/15/repeat-after-me-cabal-is-not-a-package-manager/
>   

Right. So Cabal isn't a package manager because it only manages Haskell 
packages? Not sure I agree with that definition. (It also has a laundry 
list of problems that can and should be fixed, but won't be.)

I actually spent quite a while trying to figure out what the purpose of 
Cabal *is*. It's not like it's hard to download a bunch of Haskell 
source code and utter "ghc --make Foo". So why do we even need Cabal in 
the first place? The answer, as far as I can tell, is that registering a 
library manually is so excruciatingly hard that we actually need a tool 
to automate the process. (Obviously when I first started using Haskell, 
I was mainly interested in writing runnable programs, not libraries.) 
Cabal can also run Haddock for you, which is quite hard. But it wasn't 
until cabal-install came along that I even realised that Cabal could 
track and resolve dependencies. (The fact that it doesn't track 
installed executables is news to me.)

If nothing else, I think that "what Cabal is" should be documented much 
more clearly. It took me a hell of a long time to figure this out.

Now, you say it's preferable to use the native package manager where 
possible. I've got one word for you: Windows. You know, the most popular 
OS on the market? The one installed on 98% of all computers world-wide? 
Guess what: no native package manager.

Actually, we have tools that automatically convert Cabal packages to 
Debian packages or RPMs or whatever. I think there could be some milage 
in a tool that builds Windows installers. (The problem, of course, is 
that you have to be able to *build* the library on Windows first!) You 
would of course then have all kinds of fun and games with dependency 
tracking...