private keyword dont appear to do anything

[LunaticWare]

hello, being new to D i assumed that the private keyword would 
work as in C++, but writing this code, i excepted it to throw an 
error at compile time, it appear to not doing anything, is there 
something i am doing wrong ?

------
import std.stdio;

class Foo
{
     private int id = 10;
}

struct Bar
{
     private int id = 20;
}

void main()
{
     auto foo = new Foo;
     Bar bar;

     foo.id = 15;
     bar.id = 25;

     writeln(foo.id);
     writeln(bar.id);
}

// RDMD OUTPUT
// 15
// 25