1 #include <io_utils.h>
2
3 #define OP_PRINT_INT 0
4 #define OP_PRINT_DOUBLE 1
5 #define OP_PRINT_STRING 2
6
7 typedef union Operand {
8 int int_operand; // 4
9 double double_operand; // 8
10 char *string_operand; // 8
11 } Operand;
12
13 typedef struct Instruction {
14 int operator;
15 Operand operand;
16 } Instruction;
17
18 void Process(Instruction *instruction) {
19 switch (instruction->operator) {
20 case OP_PRINT_INT: PRINT_INT(instruction->operand.int_operand);
21 break;
22 case OP_PRINT_DOUBLE: PRINT_DOUBLE(instruction->operand.double_operand);
23 break;
24 case OP_PRINT_STRING: puts(instruction->operand.string_operand);
25 break;
26 default:
27 fprintf(stderr, "Unsupported operator: %d\n", instruction->operator);
28 }
29 }
30
31 int main() {
32 PRINT_INT(sizeof(Operand));
33
34 Operand operand; // = {.int_operand=5, .double_operand=2.0};
35 operand.int_operand = 5;
36 operand.double_operand = 2.0;
37 PRINT_INT(operand.int_operand);
38 PRINT_DOUBLE(operand.double_operand);
39
40 Instruction instruction = {
41 .operator = OP_PRINT_STRING,
42 .operand = {
43 .string_operand = "Hello World!"
44 }
45 };
46
47 Process(&instruction);
48 return 0;
49 }
