https://twitter.com/aetos382/status/1052132835904040960

MakeAccessor.cs

void Main()
{
	var instance = new First {
		Second = new Second {
			Third = new Third {
				Value = 100
			}
		}
	};
	
	instance.Dump();
	
	var instanceParameter = Expression.Parameter(typeof(object));
	var valueParameter = Expression.Parameter(typeof(object));
	
	var names = new[] {
		nameof(First.Second),
		nameof(Second.Third),
		nameof(Third.Value)
	};
	
	Expression expression = Expression.Convert(instanceParameter, typeof(First));
	
	foreach (var name in names)
	{
		expression = Expression.PropertyOrField(expression, name);
	}
	
	var getterLambda = Expression.Lambda<Func<object, object>>(
		Expression.Convert(
			expression,
			typeof(object)),
		instanceParameter);
		
	getterLambda.Dump();
	
	var getterDelegate = getterLambda.Compile();
	getterDelegate(instance).Dump();
	
	var setterLambda = Expression.Lambda<Action<object, object>>(
		Expression.Assign(
			expression,
			Expression.Convert(
				valueParameter,
				typeof(int))),
		instanceParameter, valueParameter);
	
	setterLambda.Dump();

	var setterDelegate = setterLambda.Compile();
	setterDelegate(instance, 200);
	instance.Dump();
}

class First
{
	public Second Second { get; set; }
}

class Second
{
	public Third Third { get; set; }
}

class Third
{
	public int Value { get; set; }
}