Swift协议相关
1.Equable
2.Hashable
3.Comparable
4.TextOutputStream
5.TextOutputStreamable
6.CustomStringConvertible
7.LosslessStringConvertible
8.CustomDebugStringConvertible
1.Equable
2.Hashable
3.Comparable
4.TextOutputStream
5.TextOutputStreamable
6.CustomStringConvertible
7.LosslessStringConvertible
8.CustomDebugStringConvertible