lookup method
If TTMultiMap contains specified (key
, value
) pair
then return stored value.
Returned value may not be the same as value
if element type
equality does not include identity.
If key is mapped to multiple elements satisfying equality
to value
then only the first will be returned
If (key
, value
) pair is not present then returns null.
Throws ArgumentError if key
is empty or null.
Implementation
@override
V? lookup(String key, V value) =>
_root?.getKeyNode(_mapKey(key))?.lookupValue(value);