[Haskell-cafe] Transactional container for storing anonymous deletable objects

2008-12-28 Thread John Ky
Hi, I need a container data structure for storing anonymous objects - most likely things that have not value such as STM (), but probably other things as well. This will allow me to later on, iterate over the container and process those objects. Additionally I have the requirement that I need

Re: [Haskell-cafe] Transactional container for storing anonymous deletable objects

2008-12-28 Thread Luke Palmer
2008/12/28 John Ky newho...@gmail.com Hi, I need a container data structure for storing anonymous objects - most likely things that have not value such as STM (), but probably other things as well. This will allow me to later on, iterate over the container and process those objects.

Re: [Haskell-cafe] Transactional container for storing anonymous deletable objects

2008-12-28 Thread Antoine Latter
2008/12/28 Luke Palmer lrpal...@gmail.com: The hard way is a heteroeneous container, with an interface like: cons :: a - Container - IO (Key a) unlink :: Key a - Container - IO () toList :: ??? If you want to change that to: cons :: Typeable a = a - Container - IO (Key a) unlink ::

Re: [Haskell-cafe] Transactional container for storing anonymous deletable objects

2008-12-28 Thread Marc Weber
Hi John Sorry, I don't think I really grasp your problem? I think you're mixing two things: a) which data type to use to store whatever you like? * http://haskell.org/haskellwiki/Existential_type * Typable and Data.Dynamic etc.. b) Which container to use to put in stuff, return an