#include <stdio.h>
#include <stdlib.h>

#define CREATE_LABEL2(A, B) A ## B
#define CREATE_LABEL(A, B) CREATE_LABEL2(A, B)
#define for_else(A) \
    for A \
    { \
        switch (0) \
        { \
            case 0:


#define else_for \
            default: \
                goto CREATE_LABEL(__for_else_no_break_, __LINE__); \
        } \
        goto CREATE_LABEL(__for_else_break_, __LINE__); \
        CREATE_LABEL(__for_else_no_break_, __LINE__): \
        ;\
    } \
    if (0) \
    { \
        CREATE_LABEL(__for_else_break_, __LINE__): \
        ; \
    } \
    else

int main(int argc, char **argv)
{
    if (argc < 2)
    {
        fprintf(stderr, "invalid argument\n");
        return 1;
    }

    for_else ((int i = 0; argv[1][i] != 0; i++))
    {
        for_else ((volatile int j = 0; j <= i; j++))
            if (j > 5)
            {
                printf ("\n");
                break;
            }
            // /!\ this statement will be executed in the for_else loop ! better always use {}...
            printf("%d ", j); 
        else_for
            printf("\n%d <= 5!\n", i);

        if (argv[1][i] == '!')
        {
            printf("'!' detected!\n");
            break;
        }
    }
    else_for
    {
        fprintf(stderr, "invalid argument\n");
        return 1;
    }
    return 0;
}