public void SetFixedCollection(Action <World, CollectionBuilder <CommandProcessSystemBase> > build)
        {
            var cb = new CollectionBuilder <CommandProcessSystemBase>();

            build(World, cb);
            SystemProcessors = cb.Build();
        }
            public IBuilder Append(HrbcField field, FieldCollectionBuilderHandler fieldCollectionHandler)
            {
                var builder = new CollectionBuilder();

                if (content.ContainsKey(field) && content[field] != null)
                {
                    builder.Append(content[field]);
                }
                fieldCollectionHandler(builder);
                content[field] = builder.Count > 0 ? builder.Build() : null;
                return(this);
            }