Simon, We covered this extensively in the Cabal vs Haskell thread starting here: http://www.haskell.org//pipermail/libraries/2005-April/003607.html You concluded it by saying on April 22: And this observation points towards a simpler solution: rather than invisibly pre-pend the package name, just get the programmer to do so. So package P exposes a module called P.M and package Q exposes Q.M. All P's internal modules are called P.something, and similarly for Q. (We rely on some social mechanism for allocating new package names, as now.) Now of course you can import P.M and Q.M in a single module. That would be simple. It might be pretty inconvenient to say 'import Base.Data.List' rather than just 'import Data.List'. But nothing forces you to do this -- and indeed we don't do it for the current 'base' package. The point is that it's an easy way for a package author to ensure their package won't conflict with others. If they choose not to avail themselves of it, it's more likely that their package will be unusable because of accidental name conflicts. Bottom line: the current story is pretty defensible. I'm not sure that keeping names unique by implicitly using package-ids is worth the bother. http://www.haskell.org//pipermail/libraries/2005-April/003672.html It seems like you are changing your position with this proposal? Any reason for doing so? -Alex- ______________________________________________________________ S. Alexander Jacobson tel:917-770-6565 http://alexjacobson.com On Mon, 26 Jun 2006, Simon Peyton-Jones wrote:
Simon and I have been thinking about fixing this, and we think we might actually do so for GHC 6.6. Your message provoked us to write up the design. It's here http://hackage.haskell.org/trac/ghc/wiki/GhcPackages Feedback welcome
It's worth reading the old threads; for example
http://www.haskell.org//pipermail/libraries/2005-August/004281.html But there are many others!
Simon
| -----Original Message----- | From: haskell-cafe-bounces@haskell.org [mailto:haskell-cafe-bounces@haskell.org] On Behalf Of Brian | Hulley | Sent: 25 June 2006 10:16 | To: Haskell-cafe | Subject: [Haskell-cafe] Packages and modules | | Hi - | At the moment there is a problem in that two packages P and Q could contain | the same hierarchical module eg Data.Foo, and the only way for user code to | ensure the "right" Data.Foo is used is to ensure that packages P and Q are | searched in the right order. | However suppose P and Q also contain another module with the same name, eg | Data.Bar. | And suppose a user module wants to use Data.Foo from P but Data.Bar from | Q!!! _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe