<=), (>) and (>=) are defined using 'compare', not (<). Write 'compare' yourself and everything will be good. But why don't you just derive Eq and Ord for List? I didn't even think of doing that. So I will say I did this way for
On Apr 2, 2005 4:12 PM, Lemmih
Hi everyone, I defined my own list datatype and then tried to declare it as an instance of type class Ord. However when I test it with
Nil > Cons 1(Nil) I get an "ERROR - Control stack overflow"
I am under the impression that the ord class defines default implementations of (<=), (>),(>=) so that I only have to supply the implementation of (<) shown below. Can some one tell me why this does not work the way I expect it to?
Now, whereever did that interpretation come from?-)
Page 32 of Introduction to Functional Programming using Haskell. I guess thats what I deserve for trusting a dead trees :-)
The library docs are pretty clear about what constitutes a minimal definition:
http://www.haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html#t%3A...
Have a closer look at Ord and its default definitions to see what happens in your case:
http://www.haskell.org/onlinereport/basic.html#sect6.3.2
hth, claus
Thanks for the pointers to the documentation. -- Lloyd G Smith