[Haskell-beginners] Existential data types

[Brandon S. Allbery KF8NH]

On 2008 Dec 15, at 12:49, Michael Snoyman wrote:
> I believe I have come to the conclusion that what I would like to do  
> is impossible, but I would like to have that confirmed. I would  
> basically like to be able to have a heterogeneous list without  
> boxing everything in a data type. Below is the sample code, with the  
> code I would like to use commented out. I'm I missing something, or  
> does Haskell simply not support what I am trying for?


It's possible but nontrivial.  Look at HList on http://hackage.haskell.org 
  for an implementation.

-- 
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH


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