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

union Value {
    int   as_int;
    char* as_string;
};
// A union object can contain only one of the fields --- not all.
// They share the same space.

enum ValueType {
    TYPE_INT,
    TYPE_STRING
};

// Almost equivalent to this:
typedef  int  ValueType; // makes an alias type called ValueType that is equivalent to int
ValueType TYPE_INT    = 0;
ValueType TYPE_STRING = 1;

typedef struct _ValueWithType {
    union Value value;
    enum ValueType value_type;
} ValueWithType;

int main(int argc, char* argv[]) {
    //union Value v = { .as_int = 5 };
    //enum ValueType v_type = TYPE_INT;
    ValueWithType v = { .value.as_int = 5, .v_type = TYPE_INT };
    log_int( v.value.as_int );

    v.value.as_int = 7;
    log_int( v.value.as_int );

    v.value.as_string = "apple";
    v.value_type = TYPE_STRING;
    log_str( v.value.as_string );
    
    // log_int( v.as_int );  // BAD!!!  The char* overwrote the int that was there before.

    return EXIT_SUCCESS;
}
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