SplayTreeMap<K, V> 构造函数

SplayTreeMap<K, V>(
  1. [int compare(
    1. K key1,
    2. K key2
    )?,
  2. bool isValidKey(
    1. dynamic potentialKey
    )?]
)

实现

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