Splice on collections

Question

In perl, the splice function returns a new array of items from an existing array and at the same time removes these items from the existing array.

my @newarry = splice @oldarray, 0, 250;

@newarray will now contain 250 records from @oldarray and @oldarray is 250 records less.

Is there an equivalent for the C# collection classes ie Array, List, Queue, Stack with a similar function? So far I have only seen solutions where two steps are required (return + remove).

Update - no functionality exists so I have implemented an extensio method to support the Splice function:

public static List<T>Splice<T>(this List<T> Source, int Start, int Size) 
{
  List<T> retVal = Source.Skip(Start).Take(Size).ToList<T>();
  Source.RemoveRange(Start, Size);
  return retVal;
}

With the following Unit test - which succeeds:

[TestClass]
public class ListTest
{
  [TestMethod]
  public void ListsSplice()
  {
    var lst = new List<string>() {
      "one",
      "two",
      "three",
      "four",
      "five"
    };

    var newList = lst.Splice(0, 2);

    Assert.AreEqual(newList.Count, 2);
    Assert.AreEqual(lst.Count, 3);

    Assert.AreEqual(newList[0], "one");
    Assert.AreEqual(newList[1], "two");

    Assert.AreEqual(lst[0], "three");
    Assert.AreEqual(lst[1], "four");
    Assert.AreEqual(lst[2], "five");

  }
}

Answer 1

You can implement a Splice method with an extension. This method simply get a range (which is a copy of the referenced object in the list), then it removes the objects from the list.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SpliceExample
{
    class Program
    {
        static void Main(string[] args)
        {
            List<int> numbers = new List<int> { 1, 2, 3, 4, 5, 6, 7, 8, 9 };

            List<int> subset = numbers.Splice(3, 3);

            Console.WriteLine(String.Join(", ", numbers)); // Prints 1, 2, 3, 7, 8, 9
            Console.WriteLine(String.Join(", ", subset));  // Prints 4, 5, 6

            Console.ReadLine();
        }
    }

  static class MyExtensions
  {
      public static List<T> Splice<T>(this List<T> list, int index, int count)
      {
          List<T> range = list.GetRange(index, count);
          list.RemoveRange(index, count);
          return range;
      }
  }
}