Hunt.Index.IndexImpl

Heterogeneous indexes using ExistentialQuantification.

Indexes have to implement the Index type class as well as obey other constraints defined in IndexImplCon.

Note: Due to the nature of ExistentialQuantification, deserialization is tricky because the concrete implementation is not known. This is circumvented by storing the type representation of the index. Deserialization is possible if there is a matching type representation in the set of available types. This requires the use of the custom get functions.

Documentation

type IndexImplCon i = (Index i, Show i, ICon i, IndexValue (IVal i), Binary i, Typeable i, IKey i ~ Text)

Constraint for index implementations.

data IndexImpl

Index using ExistentialQuantification to allow heterogeneous index containers.

Constructors

forall i . IndexImplCon i => IndexImpl

Fields

ixImpl :: i

Instances

Show IndexImpl

Binary IndexImpl

FIXME: actually implement instance

Default IndexImpl

NFData IndexImpl

gets' :: [IndexImpl] -> Get [(Context, IndexImpl)]

Deserialize a set of IndexImpls. Requires a set of available index implementations.

Note: This will fail if a used index implementation is not provided.

get' :: [IndexImpl] -> Get IndexImpl

Deserialize an IndexImpl. Requires a set of available index implementations.

Note: This will fail if a used index implementation is not provided.

mkIndex :: IndexImplCon i => i -> IndexImpl

Wrap an index using ExistentialQuantification to allow heterogeneous containers.