TrackedBackingStore.cs

using System;
using System.Runtime.CompilerServices;

namespace Std.BasicTypes
{
    [Serializable]
    public struct TrackedBackingStore<TStoreType>
    {
        private TStoreType _value;
        private readonly PropertyTrackingManager _manager;
        private readonly int _stateIndex;

        private Func<TStoreType, TStoreType, bool> _equalOperator;

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public TrackedBackingStore(PropertyTrackingManager manager, int id,
            Func<TStoreType, TStoreType, bool> equalOperator)
            : this()
        {
            _manager = manager;
            _stateIndex = id;
            _equalOperator = equalOperator;
        }

        public TStoreType Value
        {
            [MethodImpl(MethodImplOptions.AggressiveInlining)]
            get => _value;
            [MethodImpl(MethodImplOptions.AggressiveInlining)]
            set => Set(value);
        }

        public bool HasChanged
        {
            [MethodImpl(MethodImplOptions.AggressiveInlining)]
            get => _manager.State.Get(_stateIndex);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public TStoreType Get()
        {
            return _value;
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void Set(TStoreType value)
        {
            if (_equalOperator(_value, value))
            {
                return;
            }

            _value = value;
            _manager.SetState(_stateIndex);
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public void InitializeValue(TStoreType value)
        {
            _value = value;
        }
    }
}