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

// GOAL:  Anonymous union with a typedef struct to keep it short

typedef struct {
    union {
        int   as_int;
        char* as_string;
    };  // no field name for the union inside.  ANONYMOUS UNION
    enum ValueType {
        TYPE_INT,
        TYPE_STRING
    } type;    // .type field of the struct type
} ElementSimpler;


void print_element(ElementSimpler value_with_type) {
    if(value_with_type.type == TYPE_INT) {
        printf("value is %d\n", value_with_type.as_int);
    }
    else {
        printf("value is %s\n", value_with_type.as_string);
    }
}

int main(int argc, char* argv[]) {
    ElementSimpler value_with_type = { .as_int = 5, .type = TYPE_INT };

    value_with_type.as_int = 7;
    print_element(value_with_type);  // <<<< REWARD <<<<

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

© Copyright 2023 Alexander J. Quinn         This content is protected and may not be shared, uploaded, or distributed.