On Wed, Aug 15, 2012 at 3:38 PM, Bryan O'Sullivan
I propose that the sense of the recommendation around upper bounds in the PVP be reversed: upper bounds should be specified only when there is a known problem with a new version of a depended-upon package.
I, too, agree. Here is my assortment of thoughts on the matter. Here's some bad news: with cabal 1.14 (released with Haskell Platform 2012.2), cabal init defaults to bounds like these: build-depends: base ==4.5.*, bytestring ==0.9.*, http-types ==0.6.* Also, one problem with upper bounds is that they often backfire. If version 0.2 of your package does not have upper bounds, but 0.2.1 does (because you found out about a breaking upstream change), users who try to install your package may get 0.2 instead of the latest, and still get the problem you were trying to shield against. A neat feature would be a cabal option to ignore upper bounds. With --ignore-upper-bounds, cabal would select the latest version of everything, and print a list of packages with violated upper bounds. -Joey