public bool ContainsKey(TKey key) { return(_inner.ContainsKey(key)); }
public bool ContainsKey(TKey key) => _local.ContainsKey(key) || _tryLookup(_arg, key, out var dummy);
public bool ContainsKey(TKey key) { return(_inner.ContainsKey(key)); }
public bool ContainsKey(TKey key) => _local.ContainsKey(key) || _tryLookup(_arg, key, out var dummy);