using System;
using System.Linq.Expressions;
 
 
namespace TestBench
{
	class Program
	{
		static void Main(string[] args)
		{
			ParameterExpression innerX = Expression.Parameter(typeof(int), "innerX");
			ParameterExpression outerX = Expression.Parameter(typeof(int), "outerX");
 
			//outerXとinnerXでInvokeを介してParameterの読み替えが起きている。
			var expression = Expression.Lambda<Func<int, int>>(
				Expression.Invoke(Expression.Lambda<Func<int, int>>(
				Expression.Add(innerX, innerX), innerX), outerX), outerX);
 
			Console.WriteLine(expression.Compile()(10));
 
		}
	}
}
 

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