Data.Map questions

Jean-Philippe Bernardy jeanphilippe.bernardy at
Wed Mar 30 05:57:06 EST 2005

On Tue, 29 Mar 2005 13:20:12 +0200, Johannes Waldmann
<waldmann at> wrote:
> What does Ord guarantee?
> I hope it is a total ordering compatible with  (==)
> (so that Maps could be elements of Sets etc.)
> If so, perhaps there should be a comment in the documentation.
>  From reading the source ghc-6.4/libraries/base/Data/Map.hs
> it is not clear why Eq uses toAscList but Ord uses toList -
> so perhaps there is some hidden magic?

The magic is rather simple since toList is simly aliased to
"toAscList". This is probably better changed to use toAscList.


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