如何按位与CFBitVector [英] How to bitwise-and CFBitVector

问题描述

我 CFMutableBitVector 的两个实例，像这样：

I have two instances of CFMutableBitVector, like so:

 CFBitVectorRef ref1, ref2;

我怎样才能做到逐位操作，以这些家伙？对于现在，我只关心和，但显然 XOR ，或等将是了解的。

How can I do bit-wise operations to these guys? For right now, I only care about and, but obviously xor, or, etc would be useful to know.

很明显，我可以通过矢量位重复，但似乎傻了，当我在对位电平工作。我觉得有只是一些我缺少核心基础功能，但我无法找到他们。

Obviously I can iterate through the bits in the vector, but that seems silly when I'm working at the bit level. I feel like there are just some Core Foundation functions that I'm missing, but I can't find them.

谢谢，

库尔特

推荐答案

嘛

CFBitVectorRef

是

typedef const struct __CFBitVector *CFBitVectorRef;

其是

struct __CFBitVector {
    CFRuntimeBase _base;
    CFIndex _count;         /* number of bits */
    CFIndex _capacity;  /* maximum number of bits */
    __CFBitVectorBucket *_buckets;
}; 

其中，

/* The bucket type must be unsigned, at least one byte in size, and
   a power of 2 in number of bits; bits are numbered from 0 from left
   to right (bit 0 is the most significant) */

typedef uint8_t __CFBitVectorBucket;

所以，你可以在做字节潜水可能加快速度明智的操作。当然，作为不可变可能会阻碍事情有点：D

So you can dive in a do byte wise operations which could speed things up. Of course being non-mutable might hinder things a bit :D

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