Using associated data types to create unpacked data structures

Johan Tibell johan.tibell at
Thu Aug 12 08:02:41 EDT 2010

On Thu, Aug 12, 2010 at 1:38 PM, Simon Marlow <marlowsd at> wrote:

> On 12/08/2010 12:28, Johan Tibell wrote:Sorry, I was being unclear. The
> problem is that library A can't pass a
>> MapIntDouble to library B as the types defined by the two libraries
>> aren't compatible.
> That's true, but is it really going to cause many problems in practice?
>  Which libraries have functions that take a Map argument, other than the Map
> library itself?

I've seen a few on Hackage, but I haven't run any comprehensive study. The
same problem applies to tuples, lists, sets and other data structure as

Anecdotally you see more uses of maps and other data structures as programs
get larger but by its very nature Hackage is a place for libraries, not
large programs.

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