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

// BAD WAY #3:  use integer constants to indicate type, with a typedef alias for clarity
//  - We had to make distinct values for TYPE_INT and TYPE_STRING.
//  - We had to look at those values, even though 0 and 1 don't mean any quanity.

union Value {
    int   as_int;
    char* as_string;
};
// A union object can contain only one of the fields; they share the same space.


typedef int ValueType;  // form is:  typedef  «existing_type»  «new_type_name»
ValueType TYPE_INT = 0;
ValueType TYPE_STRING = 1;

void print_element(union Value the_value, 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 };
    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: */