RedBlackTree thin wrapper initialization

[Chris via Digitalmars-d]

On Wednesday, 28 May 2014 at 07:13:37 UTC, BlackEdder wrote:
> I'm trying to write a thin wrapper around redblacktree, but it 
> seems every object of the class shares the same copy of 
> redblacktree. Am I doing something wrong or is this a bug.
>
> Minimal code example:
>
> import std.array;
> import std.container;
> import std.stdio;
>
> class A {
>     auto tree = new RedBlackTree!string();
> }
>
> unittest {
>     auto a = new A();
>     a.tree.insert( "a" );
>     auto b = new A();
>     writeln( "Should be empty, but is: ", b.tree.array );
>     writeln( "Should be empty, but has length: ", b.tree.length 
> );
> }
>
> Which results in the following output:
> $ rdmd -unittest rbt.d
> Should be empty, but is: ["a"]
> Should be empty, but has length: 1
>
>
> I'm using dmd 2.0.65.

Have you tried

class A {
   RedBlackTree!(string) tree;
   this() {
     tree = new RedBlackTree!string();
   }
}

Maybe in your implementation all instances of class A share the 
same underlying instance RedBlackTree, or class RedBlackTree was 
designed as a singleton (which would seem odd to me).

PS This question would be better suited for the "D learn" forum.