Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

C# Querying With LINQ Functional Programming in C# Lambda Expressions

My code is correct but I keep receiving an error

My code is correct but I keep receiving this error:

Bummer: Did you use the same variable names in the parameters of the lambda expression?

My code is as follows: public Action<int, Func<int, int>> DisplayResult = (int result, Func<int, int> operation) => { Console.WriteLine(operation(result)); };

Please advise.

Program.cs
using System;

namespace Treehouse.CodeChallenges
{
    public class Program
    {     
        public Func<int, int> Square = (int number) =>
        {
            return number * number;
        };

        public Action<int, Func<int, int>> DisplayResult = (int result, Func<int, int> operation) =>
        {
            Console.WriteLine(operation(result));
        };

        static void Main(string[] args)
        {

        }
    }
}

1 Answer

Steven Parker
Steven Parker
218,691 Points

The challenge is expecting you to keep the same parameter names when you refactor. The second parameter was originally named "function" but it has been changed to "operation" in this code.

Also, you don't need to declare parameter types when you write lambda expressions, the type is inferred from the function body.