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

Dougal Stanton dougal at dougalstanton.net
Tue Mar 23 06:37:24 EDT 2010

On Tue, Mar 23, 2010 at 10:00 AM, Roel van Dijk <vandijk.roel at gmail.com> wrote:
> The documentation for Data.Version might be insightful:
> http://haskell.org/ghc/docs/latest/html/libraries/base-
> 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.

This post has an answer, but not one that makes me very happy ;-)


"We've not yet removed tag from the parser for backwards compatibility.
Clearly what we should do is add a big warning (or simply error) that
such tags are no longer supported.

I hope in time to get Data.Version changed to eliminate the tags
entirely." (Duncan Coutts)

I guess it's too easy to abuse (says he who was planning to abuse it)
but it's sad that there isn't something I can easily use in its place.

At the moment renaming the package is serving my purpose.



Dougal Stanton
dougal at dougalstanton.net // http://www.dougalstanton.net

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