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CSharp · Console

/Program.cs

using System;	

static class ArrayExtensions
{
	public static int FindIndex<T>(this T[] array, Predicate<T> match)
	{
		return Array.FindIndex(array, match);
	}
}

public class Program
{
	public static void Main()
	{
		// Usage
		int[] array = { 9,8,7,6,5 };

		var index = array.FindIndex(i => i == 7);

		Console.WriteLine(index); // Prints "2"
	}
}