Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

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

Posted by Christopher Coscina
Christopher Coscina
5,611 Points

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
231,198 Points
Steven Parker
Steven Parker
231,198 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.