考虑以下代码:
#include <stdint.h>
#include <vector>
#include <iostream>
int main()
{
typedef std::vector<uint8_t> rawbytes;
rawbytes data({0xaa,0xbb,0xcc,0xdd});
rawbytes::iterator data_it = data.begin();
uint32_t as_int = (*data_it++ << 24 ) | ( *data_it++ << 16 ) | ( *data_it++ << 8 ) | *data_it++;
std::cout << std::hex << as_int << std::endl;
}
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这段代码的输出是我所期望的:
aabbccdd
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实际上,我编写了类似的代码,但我意识到我不确定它是否可以正常工作。
我对此表示怀疑:
uint32_t as_int = (*data_it++ << 24 ) | ( *data_it++ << 16 ) | ( *data_it++ << 8 ) | *data_it++;
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如果可以保证从左到右执行评估,那么意味着按此顺序进行?:
1: (*data_it++ << 24 )
2: …
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