On Apr 28, 2009, at 23:32 , michael rice wrote:

Thank guys,

Now what am I misunderstanding in the code below?

lst = [('A',65),('B',66),('C',67),('D',68)]

You didn't give a type for lst, so it defaulted to [(Char,Integer)]. This is a manifestation of the Monomorphism Restriction, invoked because lst doesn't take any arguments: it forces lst to have a definite type, so defaulting is used to fix the numeric part to Integer.

If you add a type specification for lst, things will work as you expect.

brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery@kf8nh.com

system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu

electrical and computer engineering, carnegie mellon university KF8NH