A system to destroy entities in Entitas, for all pools

Readme.md

How to use

Make sure that your DestroyComponent is added to all the pools you want it to be added to. Then add the system using pools.CreateSystem(new DestroySystem()), where pools is an instance of Pools which has all the systems you added the component to.

DestroySystem.cs

using System;
using System.Collections.Generic;
using System.Linq;
using Entitas;

public sealed class DestroySystem : ISetPools, IGroupObserverSystem
{
  public GroupObserver groupObserver
  {
    get
    {
      var poolsCount = _allPools.Length;
      var groups = new Group[poolsCount];
      var eventTypes = new GroupEventType[poolsCount];

      for (var poolIndex = 0; poolIndex < poolsCount; poolIndex++)
      {
        var pool = _allPools[poolIndex];
        var componentIndex = Array.IndexOf(pool.metaData.componentTypes, typeof(DestroyComponent));

        if (componentIndex == -1)
        {
          continue;
        }

        groups[poolIndex] = pool.GetGroup(Matcher.AllOf(componentIndex));
        eventTypes[poolIndex] = GroupEventType.OnEntityAdded;
      }

      return new GroupObserver(groups, eventTypes);
    }
  }

  private Pool[] _allPools;

  public void SetPools(Pools pools)
  {
    _allPools = pools.allPools;
  }

  public void Execute(List<Entity> entities)
  {
    foreach (var entity in entities)
    {
      _allPools.First(pool => pool.HasEntity(entity)).DestroyEntity(entity);
    }
  }
}

For Entitas 0.37.0(+) see this gist.