bimap package:Agda

Partly invertible finite maps. Time complexities are given under the assumption that all relevant instance functions, as well as arguments of function type, take constant time, and "n" is the number of keys involved in the operation.
Finite maps from k to v, with a way to quickly get from v to k for certain values of type v (those for which tag is defined). Every value of this type must satisfy biMapInvariant.
The invariant for BiMap.