Porting python's `for`/`else` to C with no `setjmp`.

for_else.c

#include <stdio.h>

#define py_for(...) _Pragma("GCC diagnostic push")_Pragma("GCC diagnostic ignored \"-Wdangling-else\"") \
	for(struct{int count; bool broke; bool once; bool copy;}py_for = {}; \
	(py_for.count < 2) && !py_for.broke; ++py_for.count)if(!py_for.count)for(__VA_ARGS__) \
	if(py_for.broke){break;}else for(py_for.once = true; (py_for.copy = py_for.broke), \
	(py_for.broke = py_for.once), py_for.once && !py_for.copy; py_for.broke = py_for.once = false)
	_Pragma("GCC diagnostic pop")
#define py_whl(...) py_for(;__VA_ARGS__;)

int main(){
	py_for(int i = 0; i < 5; ++i){
		printf("%d\n", i);
	}else{
		puts("egg");
	}
}