gcc&cpp中的"foreach values"宏

#define foreach(container, item) \
    for (auto _it = (container).begin(); _it != (container).end(); ++_it) \
        for (auto &item = *_it;;)

#define foreach(container, item) \
    for (auto &item : container)

#include<iostream>
#include<vector>

int main() {
    std::vector<int> v = {1, 2, 3, 4, 5};

    foreach(v, item) {
        std::cout<< item<< std::endl;
    }

    return 0;
}

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