Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP

EnumMap of EnumMaps.

tag: 0.2.0

Fetching latest commit…

Octocat-spinner-32-eaf2f5

Cannot retrieve the latest commit at this time

Octocat-spinner-32 Data
Octocat-spinner-32 test
Octocat-spinner-32 .gitignore
Octocat-spinner-32 LICENSE
Octocat-spinner-32 README.md
Octocat-spinner-32 Setup.hs
Octocat-spinner-32 enummapmap.cabal
README.md

EnumMapMap

Based on containers 5.0, EnumMapMap provides an EnumMap, similar to IntMap but accepting any Enum type. It also provides an EnumMap of EnumMaps type. The Key is built using an infix operator (:&) and a base type, K. A typical use might look like this:

import           EnumMapMap.Strict (EnumMapMap, (:&)(..), K(..)
import qualified EnumMapMap.Strict as EMM

data Apple = Apple {weight :: Int, Circumference :: Int}
newtype AppleID = AppleID Int
newtype TreeID = TreeID Int
newtype OrchardID = OrchardID Int

type Orchards = EnumMapMap (OrchardID :& TreeID :& K AppleID) Apple

o = OrchardID 3
t = TreeID 34
a = AppleID 1
apple = EMM.lookup (o :& t :& K a) orchards

If it is being used as a single EnumMap then the Key must have type K.

type IntMap v = EnumMapMap (K Int) v

im :: IntMap String
im = EMM.singleton (K 3) "Three"
im' = EMM.insert (K 5) "Five" im

The code ensures that only the root EnumMap can be empty. There are lazy and strict variants. Both are strict in the keys, but the strict version is strict on values as well. The data structures are the same however the key types are different for the strict and lazy versions so strict operations can be performed on a lazy EnumMapMap.

Subtrees

Whole subtrees can be operated on at a time.

tree = EMM.lookup (o &: K t) $  orchards
apple = EMM.lookup (K a) tree
newOrchards = delete (K o) $ orchards
EMM.lookup (o :& t :& K a) newOrchards == Nothing

EnumMapSet

There is also 'EnumMapSet'. The terminating key type is S instead of K.

TODO:

  • Finish operations on subtrees: alter
  • More documentation
  • More tests
  • EnumMapMap & EnumMapSet - intersectBy
  • Check that Strict really is strict and Lazy really is lazy.
  • More functions - mapMaybe, update, mergeWithKey, foldr'
  • Benchmarks
  • Optimisation
  • Replace d1..d10 with numbers
Something went wrong with that request. Please try again.