On Sun, Jan 20, 2013 at 11:39 AM, Ertugrul Söylemez
What is the state of container libraries? I am looking for a library which provides:
* unordered containers (for "operational" type safety, I don't want to impose orders on things that don't have them -- unordered containers does this)
You are imposing an order.
I mean I don't want Ord instances for types with no "natural" order. I don't mind that a container structure will impose the topological order, or that containers can be ordered by inclusion. In particular, I have datatypes whose values represent incomparable "atoms" of some type. A comparison between them should "really" yield bottom. So an Ord-based container is not appropriate. I'd rather not have an Ord instance for these types and therefore statically eliminate that bottom.
* can handled nested containers (containers does that) * can be serialized easily, or better yet, has Generic instances
Does such a library exist? What are you using for Set and Map needs?
What's wrong with 'containers' itself? I prefer Map/Set over HashMap/HashSet, because the speed difference is small and only noticable for large maps/sets. If you need multiple indices, there is IxSet.
I took a look at 'hashmap', which uses 'hashable' and 'containers' to implement hash containers. I worried about the performance, and thought I'd ask for opinions on containers. My goal is to create an IxSet-like structure which can handle unordered types, and preferably whose indices can be derived GHC.Generics-ally.