C# Programming.

The C# language: its type system, its members, its patterns and the rules the compiler enforces. Covers 16 sub-skills.

• C# Programming · 1 of 3

  Pattern matching

  What do the joining words in a pattern allow?

  Atwo values in one armBtwo arms in one testCtwo arms in one valueDtwo tests in one arm

• C# Programming · 2 of 3

  Extension methods

  Which line of that program proves the body had not yet run?

  using System;using System.Collections.Generic;using System.Linq;static class Help{    public static IEnumerable<int> Doubled(this IEnumerable<int> xs)    {        Console.WriteLine("walking");        foreach (int x in xs) yield return x * 2;    }}class P{    static void Main()    {        var q = new[] { 1, 2, 3 }.Doubled();        Console.WriteLine("built");        Console.WriteLine(string.Join(",", q));        Console.WriteLine(q.Count());    }}

  Athe second, printed from outsideBthe first, printed from outsideCthe first, printed from insideDthe second, printed from inside

• C# Programming · 3 of 3

  Lambdas

  What is the honest summary of a closure?

  Aone whole method holding the variables it namesBa method holding the values it namesCan object holding the variables it namesDan object holding the values it names