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

// BETTER WAY #1:  use enum type

union Value {  // canonical (basic) syntax.  Creates a type called 'union Value'
    int   as_int;
    char* as_string;
};
// A union object can contain only one of the fields; they share the same space.

enum ValueType {  // canonical (basic) syntax.  Creates a type called 'enum ValueType'
    TYPE_INT,
    TYPE_STRING
};

void print_element(union Value the_value, enum ValueType type_of_value) {
    if(type_of_value == TYPE_INT) {
        printf("the_value is %d\n", the_value.as_int);
    }
    else {
        printf("the_value is %s\n", the_value.as_string);
    }
}

int main(int argc, char* argv[]) {
    union Value the_value = { .as_int = 5 };
    enum ValueType type_of_value = TYPE_INT;

    the_value.as_int = 7;
    print_element(the_value, type_of_value);

    the_value.as_string = "apple";
    type_of_value = TYPE_STRING;
    print_element(the_value, type_of_value);
    
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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