BinaryHeap as member

[Era Scarecrow]

On Monday, 13 November 2017 at 16:26:20 UTC, balddenimhero wrote:
> In the course of writing a minimal example I removed more than 
> necessary in the previous pastebin (the passed IntOrder has not 
> even been used). Thus here is the corrected one: 
> https://pastebin.com/SKae08GT. I'm trying to port this to D.

  Throwing together a sample involves wrapping the value in a new 
value. Still the idea is put across...

  Not sure if this is the best way to do this, but only takes a 
little dereferencing to access the value.

Compiled w/DMD v2.069.2

[code]
import std.container.binaryheap;
import std.range : iota;
import std.array;
import std.stdio;

void main()
{
   int len = 10;
     int[] a = iota(len).array;

     auto foo = new WeightedHeap!int([0,2,4,6,8], a);

   foreach(v; foo.h)
     writeln(v.weight, "\t", *v.v);
}

struct WeightedHeap(T) {
   this(int[] order, T[] arr) {
     foreach(i, ref v; arr) {
       a ~= E(order[i%$], &v);
     }

     h = BinaryHeap!(E[])(a);
   }

   E[] a;
   BinaryHeap!(E[]) h;
//  alias h this;

   static struct E {
     int weight;
     T* v;
//    alias v this;

     int opCmp(E a) const {
       return a.weight-weight;
     }
   }
}
[/code]

Output:
Weight  Value
0       5
0       0
2       1
2       6
4       7
4       2
6       3
6       8
8       4
8       9