Beam/Beam/ImmutableState.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Beam {
    public readonly struct ImmutableState(object[] state) {
        readonly object[] state = state;

        public readonly Span<object> GetState() => state;

        public readonly State Copy()
            => new((object[])state.Clone());

        public readonly object this[Index i] {
            get => state[i];
        }

        public static implicit operator State(ImmutableState state)
            => state.Copy();
    }
}