idiomatic D: what to use instead of pointers in constructing a tree data structure?

[Laeeth Isharc via Digitalmars-d-learn]

On Wednesday, 7 January 2015 at 14:59:58 UTC, H. S. Teoh via 
Digitalmars-d-learn wrote:
> On Wed, Jan 07, 2015 at 02:52:51PM +0000, Laeeth Isharc via 
> Digitalmars-d-learn wrote:
>> Another schoolboy question.
>> 
>> Suppose I am constructing a tree (in this case it is an AST).  
>> In C I
>> would have a pointer for the child to find the parent, and an 
>> array or
>> linked list of pointers to find the children from the parent.
>> 
>> Obviously, I could still use pointers, but that would not be
>> idiomatic.
>
> Not true. If you're using a tree structure, you *should* use 
> pointers.
> Unless you're using classes, which are by-reference, in which 
> case you
> can just use the class as-is. :-)
>
>
> --T

The GC is allowed to move structs around, as I undestand it.  
Under what circumstances do I get into trouble having a pointer 
to them?