An efficient builder that can be used to construct a multivalued map
with successive add calls, which is more efficient than doing so
directly due to the builder's deferred sorting.
structMultiValueMap(KeyType, ValueType, alias KeySort = (a, b) => a < b)
An efficient builder that can be used to construct a multivalued map with successive add calls, which is more efficient than doing so directly due to the builder's deferred sorting.