[Haskell-cafe] Cabal pre-compiled packages

[Daniel Fischer]

Am Samstag 27 Februar 2010 16:39:27 schrieb Andrew Coppin:
> Diego Souza wrote:
> > Hi,
> >
> > currently when one install a cabal package it compiles it and then
> > install generated binaries. I wonder whether or not it would be useful
> > to have pre-compiled binaries as many package managers usually do
> > (e.g. apt). I often think that would save some time on the expense of
> > a busier hackage server capable of generating packages for many
> > different platforms.
> >
> > I'm particularly thinking on the following scenario: suppose that you
> > have code that is ready for production. If cabal supported
> > pre-compiled binaries, there is no need to install ghc or eventually
> > any other compiler, just runtime environment and eventually cabal. I
> > must say that I have no experience in doing this in Haskell (just
> > personal/small projects), so I suppose one have to generate binaries
> > and use other sort of package manager to deploy code to production
> > (which sounds reasonable as well). Thus, if the assumption is correct,
> > cabal is a development tool, not something one could to only deploy
> > runtime-only packages.
> >
> > I also would appreciate if others could share how usually this is
> > managed.
>
> As far as I know, Cabal is mainly used for deploying Haskell libraries.

Yes, Cabal: Common Architecture for Building Applications and Libraries

> If you want to deploy a finished Haskell program, just compile it into
> an executable program and make it downloadable from somewhere. (Much

And since the binary doesn't need to be built anymore, you don't need Cabal 
or cabal for that. Of course, a central repo for binaries might be a good 
thing.

> like a C program or any other kind of program.) For example, if you hunt
> around, you can find Darcs available as a binary download (even for
> Windows).

Actually, I think you'll find more binaries for Windows than for *n*x, 
since commi ( ./configure && make && make install) is so simple.

>
> It might be nice if certain Haskell libraries were available in binary
> form. The trouble is, Haskell libraries have to be recompiled for each
> version of the compiler. This is why it's usually released in source
> form; otherwise you have to make a bazillion different binaries, one for
> every version of GHC on every platform that GHC runs on.

That, and it's so much better to have the source around.
Need a small modification of/addition to a library?
Unpack, edit, bump version, build, install, offer patch to maintainer.
How would you go about it if you only had the binary?

> Much easier to
> just compile from source, Unix-style. (And I've only come across one
> Haskell package that takes more than 11 seconds to compile anyway.)

So you've tried at most one of the GUI libraries, HPDF or highlighting-
kate?