copying the targets of pointers

[monarch_dodra]

On Friday, 27 July 2012 at 16:47:47 UTC, Artur Skawina wrote:
> On 07/27/12 18:11, monarch_dodra wrote:
>> This is going to sound stupid, but how do you have two 
>> pointers' targets copy each other? since pointers are used 
>> like reference types, how do you write the C++ equivalent of 
>> "*p1 == *p2"
>
> Exactly the same, there's no difference between C and D 
> pointers, except for classes.
>
>> Here is the context of what I'm trying to do:
>> 
>> ----
>> struct S
>> {
>>   struct Payload
>>   {}
>>   Payload payload;
>> 
>>   @property
>>   typeof(this) dup()
>>   {
>>     typeof(this) ret;
>>     if(payload)
>>     {
>>       ret.payload = new Payload;
>>       ret.payload = payload; //Copies the payload? The pointer?
>
> 'ret.payload' is 'S'; 'new Payload' is '*S'...
>
> If you meant 'Payload* payload;', then just the pointer is 
> copied.
>
> artur

Dang it, yes, I meant:
>   struct Payload
>   {}
>   Payload* payload;

And I want to copy the value pointed by payload. Not the pointer.

I'm kind of confused, because every time I see pointer usage, the 
deference operator is omitted?

For example:

--------
struct S
{
     void foo(){};
}

S* p = new S();
p.foo();
--------

When and where can/should/shouldn't I dereference?