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@mejedi
Created July 2, 2013 10:55
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#include <cstddef>
template<size_t n>
struct cn {
char data[n+1];
};
template<typename id, size_t index, size_t val>
cn<val> magic(id, cn<index>, cn<val>);
#define counter_read(id) \
(sizeof( \
magic(id(), cn<1>(), \
magic(id(), cn<2>(), \
magic(id(), cn<4>(), \
magic(id(), cn<8>(), \
magic(id(), cn<16>(), \
magic(id(), cn<32>(), \
magic(id(), cn<64>(), \
magic(id(), cn<128>(), cn<0>())))))))))-1)
#define counter_inc(id) \
cn<counter_read(id)+1> magic(id, \
cn<(counter_read(id)+1)&~counter_read(id)>, \
cn<(counter_read(id)+1)&counter_read(id)>)
struct my_cnt {};
size_t const a = counter_read( my_cnt );
counter_inc( my_cnt );
counter_inc( my_cnt );
counter_inc( my_cnt );
counter_inc( my_cnt );
counter_inc( my_cnt );
size_t const b = counter_read( my_cnt );
counter_inc( my_cnt );
#include <iostream>
int main() {
std::cout << a << ' ' << b << '\n';
std::cout << counter_read( my_cnt ) << '\n';
}
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