What do mean @escaping and @nonescaping closures in Swift?

在 Swift closure 中,nonescaping 是默认的,当 closure 作为参数传入的时候,当函数执行完毕后,closure 则随着函数一起在内存中消失,不再存在。

但是在一些场景中,如异步任务和需要将 closure 存储以做后续使用时,则需要将 closure 逃逸出(escaping)当前的函数,以便主体函数推出后,closure 仍然停留在内存中完成后续任务或供其他函数调用。

What do mean @escaping and @nonescaping closures in Swift?

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