c++ 特殊符号

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What does the caret in objective C mean?

ie.

void (^handler)(NSInteger);

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It depends on the context. In the example you show, it's used to denote a Block. The caret symbol is also thebitwise XOR operatorin C-based languages — that's what most programmers would identify it as, so it's good to understand that it can be both depending on where it appears, much like*, etc.

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