Heterogenous map with type-level key/value associations that are fixed by an arbitrary
relation R.
HMaps extend Poly and hence are also polymorphic function values with type-specific
cases corresponding to the map's type-level key/value associations.
Heterogenous map with type-level key/value associations that are fixed by an arbitrary relation
R
.HMap
s extendPoly
and hence are also polymorphic function values with type-specific cases corresponding to the map's type-level key/value associations.