1

Managed Languages in VS2010

Mike TaultyDeveloper & Platform GroupMicrosoft LtdMike.Taulty@microsoft.com http://www.mtaulty.com (/DevWeek.zip)

Format of the session

11

22

33

Before we get started...

What’s been going on with Visual Basic and C# since 2002?

Future commitment (from PDC 2008)“Co-Evolution” of these 2 languagesMajor features to surface in both languages

( small print – “not necessarily in the same way” )

2002 2005 2007 2009

Visual Basic 10

11

5

Visual Basic 10 Additions

C# 4.0

22

7

C# 4.0 Additions

Combined Additions

33

Dynamic Programming in VS 2008

Many places in .NET where we need to interact with “dynamic objects”

Reflection over .NET typesIDispatch invocation of COM typesIntegrating with from .NET DLR language typesIntegrating with the HTML DOM in Silverlight

TodaySome of this work is done in languagesSome of it in APIsNo consistent way of dealing with these scenarios

Dynamic Programming in VS 2008( taking Reflection as one example )

Compiler

Generates reflection-based goo

Compiler

Does not generate anything Does not generate anything

Dynamic Programming in VS 2010

Generated CodeUses System.Dynamic

Compiler Compiler

Like object but with dynamic method resolution & dispatch

Plain CLR Plain CLR Object?Object?

IDispatchIDispatchCOM COM

object?object?Implementation of Implementation of IDynamicObject?IDynamicObject?

Run-Run-timetimetype?type?

12

Dynamic types in C# 4, VB 10

Variance with Generic Types

Applies to generic interfaces and delegatesUsing interfaces as an example;

Access through a “base Access through a “base interface”interface”

Access through a “derived Access through a “derived interface”interface”

NB: Snippets compile but (intentionally) throw at runtime in VS2008 here

Strings are objects?Strings are objects?

Variance with Generic TypesConcrete Examples

NB: Snippets compile but (intentionally) throw at runtime in VS2008 here

Strings are objects?Strings are objects?

Safe if the caller cannot pass object references to the implementation

Safe if the implementation cannot pass object references to the caller

Variance with Generic Types

New syntax in C# 4 and VB 10 to indicate how a generic parameter is used by the interface

16

Variance in generic types

COM Interoperability in VS 2008

Usual scheme for working with COM types

COM TLB or DLL

Visual Studio ortlbimp.exe convertsall contained types,interfaces, etc.

Interop Assembly

ProgId()CoClass()...

.NETCode

ReferenceInterop assembly needs also deploying.Can be painful.Can be more painful for Primary Interop Assemblies (PIAs)Can be more painful for Office PIAs.

COM Interoperability in VS 2010

Revised scheme for working with COM types

Compiler option to copy COM interop typesused by code into output assemblyInterop

Assembly

.NETCode

Reference

Type 3Type 3Type 4Type 4

Type 1Type 1

Type 2Type 2

Type 1Type 1Type 2Type 2Type 3Type 3Type 4Type 4

ResultingAssembly

COM Interoperability in C# 4

COM code is littered with VARIANT typesespecially code written in VB or targetting VB

With Visual Studio < 2010Generated interop code used object for VARIANT

With Visual Studio 2010Choose to embed interop code in assemblySignatures are rewritten to use dynamic rather than object

20

COM Interoperability

Format of the session

11

22

33

Visual F#

Shipping for the first time in Visual Studio 2010

Session at 14:00 on Thursday“Taking efficiency one step further – F#”Oliver Sturm

References

“C# Futures”“VB Futures”“The Future of C#” “Future Directions for Visual Basic”

© 2008 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS,

IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.