Immutable 仅可在 Object.h 中使用，而且正逐步淘汰，请不要在新的结构体上使用！
Immutable
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Immutable 仅可在 Object.h 中使用，而且正逐步淘汰，请不要在新的结构体上使用！
Ask questions and help your peers Developer Forums
Write your own tutorials or read those from others Learning Library