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



typedef struct {
    union { 
        int as_number;   // 4 bytes
        char* as_string; // 8 bytes
    } value;
    enum {
        VALUE_INT,
        VALUE_STRING
    } type;
} IntOrString;

#define log_size(n) printf("sizeof(%s) == %ld\n", #n, sizeof(n))
#define log_int(n) printf("%s == %d\n", #n, n)
#define log_str(n) printf("%s == \"%s\"\n", #n, n)

void print_int_or_string(IntOrString value) {
    switch(value.type) {
        case VALUE_INT:
            printf("Value is %d\n", value.value.as_number);
            break;
        case VALUE_STRING:
            printf("Value is %s\n", value.value.as_string);
            break;
    }
}

int main(int argc, char* argv[]) {
    log_size(IntOrString);

    IntOrString value = {
        .value.as_number = 7,
        .type = VALUE_INT
    };
    print_int_or_string(value);
    IntOrString value2 = {
        .value.as_string = "Hello World",
        .type = VALUE_STRING
    };
    print_int_or_string(value2);

    value2.value.as_number = 81;
    value2.type = VALUE_INT;
    print_int_or_string(value2);

    value = (IntOrString){
        .value.as_string = "ECE 264",
        .type = VALUE_STRING
    };
    print_int_or_string(value);
    
    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

© Copyright 2024 Alexander J. Quinn & David Burnett         This content is protected and may not be shared, uploaded, or distributed.