Re: [Haskell-cafe] developing against privately patched libraries, and cabal

The documentation for Data.Version might be insightful: http://haskell.org/ghc/docs/latest/html/libraries/base-4.2.0.0/Data-Version.... If Cabal uses the parseVersion function to parse versions then the following version is valid: "1.2.3-a-b-c". If should result in this value: Version {versionBranch = [1,2,3], versionTags = ["a", "b", "c"]} But I don't know if Cabal allows you to depend on such a version.