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

struct IntOrString {
    // anonymous union declared as part of the struct
    union {
        char* as_string;
        int as_int;
    } ios;
    // anonymous enum declared as part of the struct
    enum {
        TYPE_STRING,
        TYPE_INT
    } type;
};

void print_int_or_string(struct IntOrString ioss) {
    if (ioss.type == TYPE_STRING) {
        printf("ios.as_string == %s\n", ioss.ios.as_string);
    } else if (ioss.type == TYPE_INT) {
        printf("ios.as_int == %d\n", ioss.ios.as_int);
    }
}

int main(int argc, char* argv[]) {
    struct IntOrString five = {
        .ios.as_int = 5,
        .type = TYPE_INT
    };

    print_int_or_string(five);

    five.ios.as_string = "five";
    five.type = TYPE_STRING;
    print_int_or_string(five);

    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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