[Haskell-cafe] Cabal-1.10.1.0 and bytestring-0.9.2.0 hackage problem.

[Albert Y. C. Lai]

On 11-08-25 10:42 AM, Bertram Felgenhauer wrote:
> (or rebuild Cabal / cabal-install starting with
> 'cabal unpack Cabal; cabal unpack cabal-install')

Replacing Cabal will break bin-package-db.

Breaking bin-package-db will break ghc (the GHC API).

"Break" means you likely don't run into problems right now, but several 
weeks later, you try to "cabal install" a package that depends on some 
of the above, and you get a nonsensical error message, and you don't 
even suspect it all started with replacing a package several weeks ago 
(you likely even forget that you did it).

See my http://www.vex.net/~trebla/haskell/sicp.xhtml , in particular the 
"pigeon drop con" scenerio.