Hi. I started my first program in D (I have a little experience in c).
I wanted to create an array of pointers for creating a node with multiple
connections. In C you can make one directly (node *nedePtr[]). What is the equivalent for the D's syntax??

Regards
Arjan

On Thursday, 16 January 2014 at 08:55:43 UTC, Arjan Fetahu wrote:
> Hi. I started my first program in D (I have a little experience in c).
> I wanted to create an array of pointers for creating a node with multiple
> connections. In C you can make one directly (node *nedePtr[]). What is the equivalent for the D's syntax??
>
> Regards
> Arjan

node*[] nedePtr;

On Thursday, 16 January 2014 at 09:00:18 UTC, Namespace wrote:
> On Thursday, 16 January 2014 at 08:55:43 UTC, Arjan Fetahu wrote:
>> Hi. I started my first program in D (I have a little experience in c).
>> I wanted to create an array of pointers for creating a node with multiple
>> connections. In C you can make one directly (node *nedePtr[]). What is the equivalent for the D's syntax??
>>
>> Regards
>> Arjan
>
> node*[] nedePtr;

Ok. Thank You!

On Thursday, 16 January 2014 at 09:03:00 UTC, Arjan Fetahu wrote:
> On Thursday, 16 January 2014 at 09:00:18 UTC, Namespace wrote:
>> On Thursday, 16 January 2014 at 08:55:43 UTC, Arjan Fetahu wrote:
>>> Hi. I started my first program in D (I have a little experience in c).
>>> I wanted to create an array of pointers for creating a node with multiple
>>> connections. In C you can make one directly (node *nedePtr[]). What is the equivalent for the D's syntax??
>>>
>>> Regards
>>> Arjan
>>
>> node*[] nedePtr;
>
> Ok. Thank You!

Keep in mind that, unlike in c++, D classes are reference types:

class Node
{
    Node[] nodes; // This is valid
}

Structs are value types though, so using a struct in the above example is illegal.

On Thursday, 16 January 2014 at 09:47:21 UTC, Rene Zwanenburg wrote:
> On Thursday, 16 January 2014 at 09:03:00 UTC, Arjan Fetahu wrote:
>> On Thursday, 16 January 2014 at 09:00:18 UTC, Namespace wrote:
>>> On Thursday, 16 January 2014 at 08:55:43 UTC, Arjan Fetahu wrote:
>>>> Hi. I started my first program in D (I have a little experience in c).
>>>> I wanted to create an array of pointers for creating a node with multiple
>>>> connections. In C you can make one directly (node *nedePtr[]). What is the equivalent for the D's syntax??
>>>>
>>>> Regards
>>>> Arjan
>>>
>>> node*[] nedePtr;
>>
>> Ok. Thank You!
>
> Keep in mind that, unlike in c++, D classes are reference types:
>
> class Node
> {
>     Node[] nodes; // This is valid
> }
>
> Structs are value types though, so using a struct in the above example is illegal.

You mean:
----
struct Node {
    Node[] nodes;
}
----

or

----
struct Node {
    Node*[] nodes;
}
----

? Works both.

What's not working is this:
----
struct Node {
	Node node;
}
----

On Thu, Jan 16, 2014 at 10:47 AM, Rene Zwanenburg <renezwanenburg@gmail.com> wrote:

> Keep in mind that, unlike in c++, D classes are reference types:
>
> class Node
> {
>     Node[] nodes; // This is valid
> }
>
> Structs are value types though, so using a struct in the above example is illegal.

That's not true. Indeed:

`struct Node { T value; Node[] children;}`

is my standard way of having trees in D.

The thing is, an array is a reference type and so the compiler is able to determine `Node` size (T.sizeof + a pointer size, or maybe 2, I don't remember which).

>> Keep in mind that, unlike in c++, D classes are reference types:
>>
>> class Node
>> {
>>    Node[] nodes; // This is valid
>> }
>>
>> Structs are value types though, so using a struct in the above example is illegal.
>
> You mean:
> ----
> struct Node {
>     Node[] nodes;
> }
> ----
>
> or
>
> ----
> struct Node {
>     Node*[] nodes;
> }
> ----
>
> ? Works both.
>
> What's not working is this:
> ----
> struct Node {
> 	Node node;
> }
> ----

I wanted to heap allocate Nodes which connect to each other via pointers. Since each Node connects to multiple others i came up with this solution.

class Node {
     auto content;
     Node*[] nodes;
     //..constructor..
}

Arjan Fetahu:

> Since each Node connects to multiple others i came up with this solution.
>
> class Node {
>      auto content;
>      Node*[] nodes;
>      //..constructor..
> }

Nodes are reference types in D, so probably you don't need to use a * for Node. Alternatively use a struct handled by pointer.

"auto content;" can't compile, you need a type, or you have to template Node on T and use it for content.

Bye,
bearophile

> Nodes are reference types in D, so probably you don't need to use a * for Node. Alternatively use a struct handled by pointer.
>
> "auto content;" can't compile, you need a type, or you have to template Node on T and use it for content.
>
> Bye,
> bearophile

Youre right, it compiles now, and the object generated is of the same size.
I'm still confusing with C. I have some experience with C experience, so I still have to learn tamplates.

Thaks for the help.

Arjan

On Saturday, 18 January 2014 at 14:57:39 UTC, Arjan Fetahu wrote:
> I have some experience with C experience, so I still have to learn tamplates.
>
> Thaks for the help.
>
> Arjan

Here's a handy introduction: http://nomad.so/2013/07/templates-in-d-explained/