Am Donnerstag, 15. Dezember 2005 09:21 schrieb Ketil Malde:
[...] Anyway, I expect most users to install via OS packages (rpm,deb,..), and distributions tend to have their own solutions for this kind of thing (/etc/alternatives springs to mind).
Yes, this is definitely the way to go. We should not try to duplicate existing functionality, probably in a much inferior way. All major Linux distributions (SuSE, Fedora, Debian, ...) use update-alternatives or a home-grown variation of this. Our OS packages should use this to existing mechanism and leave decisions like replacing or not to the underlying package manager and configuration files. I have to admit that I have been too lazy to fix the RPM .spec files in the repository to use update-alternative... :-] Let's see if I can find some time.
'runhaskell' could perhaps also be a small script that checks for the availability of 'runhugs', 'runghc', etc. This way, it could be the same for all Haskell implementations, and the choice could be configurable on a user basis (rather than per system). It would cost a bit of startup time, though.
That's again duplication: runhaskell is simply a link to the "real" executable and is under control of a cleanly separated mechanism like update-alternatives, no script hackery needed. The mechanism to make this configurable per-user is ~/bin/ and/or PATH, so there is no need to complicate things. I've been talking about Linux and *nix only above, but I'm sure other platforms have similar mechanisms. Cheers, S.