Why would you make a struct without typedef?

Question

Since I cut my teeth on code with OO, I’m biased toward using structs as classes without methods. However, there’s probably a good reason that typedef isn’t the default behavior of struct. What is it?

Answer 1

C doesn't offer custom namespaces as C++ does, but it's untrue that C doesn't have namespaces at all. Functions and structures are in different namespaces:

#include <stdio.h>

void Test ( ) {
    printf("Hello World\n");
}

struct Test {
    int field1;
    int field2;
};

int main ( ) {
    struct Test t = { 0, 1 };
    Test();
    return 0;
}

When you typedef, you are forcing structures into the same namespace as functions:

#include <stdio.h>

typedef struct {
    int field1;
    int field2;
} Test;

void Test ( ) {
    printf("Hello World\n");
}

int main ( ) {
    Test t = { 0, 1 };
    Test();
    return 0;
}

results in

main.c:8:6: error: ‘Test’ redeclared as different kind of symbol
 void Test ( ) {
      ^~~~
main.c:6:3: note: previous declaration of ‘Test’ was here
 } Test;