快速访问可变长度数组

您可以创建一个从给定地址开始并具有给定元素数量的缓冲区指针：

let buffers = UnsafeBufferPointer<AudioBuffer>(start: &bufferList.memory.mBuffers,    count: Int(bufferList.memory.mNumberBuffers))for buf in buffers {    // ...}

Swift 3（及更高版本）的更新：

let buffers = UnsafeBufferPointer<AudioBuffer>(start: &bufferList.pointee.mBuffers,    count: Int(bufferList.pointee.mNumberBuffers))for buf in buffers {    // ...}