Data.MultiMap

This datastructure represents a `k -> Set v` mapping: that is to say, each key can have multiple values (but no duplicates). Additionally, we provide some operations to reverse this mapping.

In KMonad we use this exclusively to easily define multiple names for the same Keycode in a reversible manner.

Types

data MultiMap k v

The MultiMap, which describes a one to many (unique) mapping

Instances

(Show k, Show v) => Show (MultiMap k v)

Defined in Data.MultiMap

Methods

showsPrec :: Int -> MultiMap k v -> ShowS

show :: MultiMap k v -> String

showList :: [MultiMap k v] -> ShowS

CanMM k v => Semigroup (MultiMap k v)

Defined in Data.MultiMap

Methods

(<>) :: MultiMap k v -> MultiMap k v -> MultiMap k v

sconcat :: NonEmpty (MultiMap k v) -> MultiMap k v

stimes :: Integral b => b -> MultiMap k v -> MultiMap k v

CanMM k v => Monoid (MultiMap k v)

Defined in Data.MultiMap

Methods

mempty :: MultiMap k v

mappend :: MultiMap k v -> MultiMap k v -> MultiMap k v

mconcat :: [MultiMap k v] -> MultiMap k v

CanMM k v => Ixed (MultiMap k v)

Defined in Data.MultiMap

Methods

ix :: Index (MultiMap k v) -> Traversal' (MultiMap k v) (IxValue (MultiMap k v))

CanMM k v => At (MultiMap k v)

Defined in Data.MultiMap

Methods

at :: Index (MultiMap k v) -> Lens' (MultiMap k v) (Maybe (IxValue (MultiMap k v)))

type Index (MultiMap k v)

Defined in Data.MultiMap

type Index (MultiMap k v) = k

type IxValue (MultiMap k v)

Defined in Data.MultiMap

type IxValue (MultiMap k v) = HashSet v

mkMultiMap :: (Foldable t1, Foldable t2, CanMM k v) => t1 (k, t2 v) -> MultiMap k v

Create a new multimap from a foldable of (k, foldable v) pairs.

fromSingletons :: (Foldable t, CanMM k v) => t (k, v) -> MultiMap k v

Create a new multimap from a foldable of (k, v) pairs

Operations on MultiMaps

itemed :: CanMM k v => Fold (MultiMap k v) (k, v)

A fold over all the (k, v) pairs in a MultiMap

reverse :: (CanMM k v, CanMM v k) => MultiMap k v -> MultiMap v k

Reverse a MultiMap. Note: this is not necessarily a lossless conversion.