A presentation of the .NET Foundation, followed with a description of future versions of .NET, C#6 features, and possible C#7 features.

1. .NET Foundation
The future of .NET & C#
Martin Woodward, Bertrand Le Roy

3. martin@dotnetfoudation.org
@martinwoodward
http://dotnetfoundation.org
http://github.com/dotnet
Martin Woodward

4. I live here

5. I work here

8. The .NET Foundation
.NET API for Hadoop WebClient
.NET Compiler Platform ("Roslyn")
.NET Map Reduce API for Hadoop
.NET Micro Framework
ASP.NET MVC
ASP.NET Web API
ASP.NET Web Pages
ASP.NET SignalR
MVVM Light Toolkit
.NET Core 5
Orleans
MEF (Managed Extensibility Framework)
OWIN Authentication MiddlewareRx (Reactive Extensions)
Orchard CMS
Windows Azure .NET SDK
Thinktecture IdentityManager
WnsRecipe
Mimekit Xamarin.Auth
Xamarin.Mobile
Couchbase for .NET
Meet the people behind the .NET Foundation
http://www.dotnetfoundation.org/teamhttp://www.dotnetfoundation.org
@dotnetfdn
Mailkit
System.Drawing
ASP.NET 5
Salesforce Toolkits for .NET
NuGetKudu
Cecil
MSBuild
LLILC
Prism
WorldWide Telescope
Microsoft Confidential

9. Practices Visibility
Mentorship
Support
Governance
Feedback
Media
Events
Fostering a vibrant .NET ecosystem
Protection
Licenses
Copyrights
Trademarks
Patents
dotnetfoundation.org
dotnet.github.io
@dotnetfdn
Openness.
Community.
Rapid innovation.

10. .NET Foundation Support Services
• CLA Automation (inc self-service admin)
• Domain Registration
• DNS Management
• SSL Certs
• Authenticode Code Signing
• Secret Management
• Financial Authority
• Forums
• Email
• MSDN
• Swag

13. Microsoft Confidential

14. .NET Innovation Cross-PlatformOpen Source
The road ahead for .NET
.NET Core
ASP.NET 5

15. .NET 2015
.NET Framework: Windows & full BCL
.NET Core: cross-platform & open-source

16. .NET Framework
• Windows
• ASP.NET 5
• ASP.NET 4.6
• WPF
• Windows Forms

17. .NET Core
• Cross-platform
• 100% open-source
• Application-local framework
• Modular, using NuGet

18. .NET Native
• Compiled to native code
• Universal Windows Platform (UWP) apps
• IoT devices, Mobile, PC, Xbox, Surface Hub

19. .NET Cross Platform
• Linux: .NET Core + VS Code + OmniSharp
• OSX: .NET Core + VS Code + OmniSharp
• iOS & Android: Xamarin
• Windows: .NET Framework, Core, VS, VS Code, OmniSharp

20. .NET Open Source
• .NET Core: CoreFx and CoreCLR
• Full stack of C#, VB, and F#

21. C# Design Process
• Design meetings up to 4 times a week
• Design reviews once a month
• Proposals and design notes on GitHub
• Prototypes for early feedback

22. C# Evolution
C# 1
Hello World
C# 2
Generics
C# 3
Linq
C# 4
Dynamic
C# 5
Async
C# 6
Boilerplate
C# 7
???

23. Roslyn: Great for consumers
• Delightful IDE experiences
• Code-aware libraries
• A new generation of code analysis

24. Roslyn: Great for extenders
• Rich APIs for understanding code
• Analyzer and code fix framework

25. Roslyn: Great for us
• Written in C#
• Beautiful architecture
• Less duplication between layers
• A lot easier to write new features

26. C# 6 auto-property initializers
public string FirstName { get; set; } = "Jane";

27. C# 6 getter-only auto-properties
public string FullName { get; } = "Jane Doe";
public Person(string first, string last)
{
FullName = first + " " + last;
}

28. C# 6 expression-bodied members
public void Print() => Console.WriteLine(FullName);
public string FullName => First + " " + Last;

29. C# 6 using static
using static Console;
using static System.DayOfWeek;
WriteLine(Wednesday – Monday);

30. C# 6 null-conditional operators
if (json?["x"]?.Type == JTokenType.Integer &&
json?["y"]?.Type == JTokenType.Integer)
{
return new Point((int)json["x"], (int) json["y"]);
}
return null;

31. C# 6 string interpolation
var s = $"http://weblogs.asp.net/{blog}/{slug}";
Console.WriteLine($"({point.X}, {point.Y})");

32. C# 6 nameof
public Point Add(Point point)
{
if (point == null)
{
throw new ArgumentNullException(nameof(point));
}
}

33. C# 6 index initializers
return new JObject { ["x"] = X, ["y"] = Y };

34. C# 6 exception filters & await in catch
try { … }
catch (SomeException e) when (e.IsCatastrophic)
{
await LogAsync(e);
}
finally
{
await CloseAsync();
}

35. C# 7 Competition
• Java
• “Systems”: Go, Rust, D, …
• “Functional”: F#, Scala, Erlang, Clojure, …
• “Compute”: Python, R, Matlab
• JavaScript
• Swift

36. Trends to watch for C# 7
• Cloud & devices
• Wire data
• Performance
• Asynchrony

37. Pattern matching
if (o is Point p && p.X == 5) { WriteLine(p.Y); }
if (o is Point{ X is 5, Y is var y }) { WriteLine(y); }
if (o is Point(5, var y)) { WriteLine(y); }

38. Patterns in switch statements
switch (o)
{
case string s:
Console.WriteLine(s);
break;
case int i:
Console.WriteLine($"Number {i}");
break;
case Point(int x, int y):
Console.WriteLine($"({x},{y})");
break;
case null:
Console.WriteLine("<null>");
break;
}

39. Tuple types
public (int sum, int count) Tally(IEnumerable<int> values) { … }
var t = Tally(myValues);
Console.WriteLine($"Sum: {t.sum}, count: {t.count}");
public async Task<(int sum, int count)> TallyAsync(IEnumerable<int> values) { … }
var t = await TallyAsync(myValues);
Console.WriteLine($"Sum: {t.sum}, count: {t.count}");

40. Tuple literals
public (int sum, int count) Tally(IEnumerable<int> values)
{
var s = 0; var c = 0;
foreach (var value in values) { s += value; c++; }
return (s, c);
}
public (int sum, int count) Tally(IEnumerable<int> values)
{
var res = (sum: 0, count: 0);
foreach (var value in values) { res.sum += value; res.count++; }
return res;
}

41. Nullable and non-nullable reference types
string? n; // Nullable reference type
string s; // Non-nullable reference type
n = null; // Sure; it's nullable
s = null; // Warning! Shouldn’t be null!
s = n; // Warning! Really!
WriteLine(s.Length); // Sure; it’s not null
WriteLine(n.Length); // Warning! Could be null!
if (n != null) { WriteLine(n.Length); } // Sure; you checked

42. Local functions
IEnumerable<T> Filter<T>(IEnumerable<T> source, Func<T, bool> predicate)
{
if (source == null) throw new ArgumentNullException(nameof(source));
if (predicate == null) throw new ArgumentNullException(nameof(predicate));
IEnumerable<T> Iterator()
{
foreach (var element in source)
if (predicate(element))
yield return element;
}
return Iterator();
}

43. Other top feature ideas
Shorthand “record” types
Preferably with subclasses
Support immutable records and non-destructive mutation
Extension “everything”
Great partner feature to pattern matching
Typed “views” of wire data
Like TypeScript types? Like F# type providers?
Ref returns and array slices
For performance-critical code
Async collections and streams
Async iterators and async foreach?