Cabal: Odd Error Message + Lack of Documentation

Question

So I recently installed cabal (from the default binary of ArchLinux). I then tried to upgrade cabal as a user:

cabal upgrade Cabal --user --prefix=$USER
Resolving dependencies...
cabal: fromFlag NoFlag. Use fromFlagOrDefault

What I've already done:

1. Googled the error message. Turned up the cabal source and little else.
2. Looked at haskell-wiki on cabal-install.
3. Looked through this guide.

So basically I'm wondering:

• What's up with the error message?
• Could anyone point me in the direction of a cabal tutorial?

Answer 1

I think that's a bug in Arch's package. I'm running Arch as well, and I got the same error.

I then built cabal-install (0.8.2) from Hackage, which didn't complain when I run cabal upgrade Cabal. In fact, it started building right away, although I didn't let it finish because I didn't feel comfortable upgrading a core package.

May I ask why you wanted to upgrade Cabal? The version that comes with ghc is 1.8.0.2, and the latest version is 1.8.0.4 -- not too distant IMO. Besides, if you're running cabal-install as normal user, why not simply cabal install? It doesn't have permission to overwrite the system files anyway.