Implementation
SplayTreeMap([
int Function(K key1, K key2)? compare,
bool Function(dynamic potentialKey)? isValidKey,
]) : _compare = compare ?? _defaultCompare<K>(),
_validKey = isValidKey;
SplayTreeMap([
int Function(K key1, K key2)? compare,
bool Function(dynamic potentialKey)? isValidKey,
]) : _compare = compare ?? _defaultCompare<K>(),
_validKey = isValidKey;