For "my" developer lunch i selected an awesome session from Microsoft PDC09, called Evolving ADO.NET Entity Framework in .NET 4 and Beyond, where Microsoft's Shyam Pather and Chris Anderson takes us through an hour of as many new features in the new Entity Framework as possible.

Especially interesting is the ability to use POCO-classes (Plain Old CLR Objects) and the "Model first" concept where you remove the dependency to any base classes and begin with the logic tier. Also, with the embedding of LinqToSql into Entity Framework, the rendering of SQL-clauses and implementation of Stored Procedures in the context really takes the data access layer to a new level and remove many pitfalls seen in the past with OR mappers.

Adding to this with the ability to test applications with fake repositories and such i think this is the way to build applications for quite a while.

For this weeks developer lunch I thought I would pick a seminar I saw at TechDays 2009 here in Sweden.

It was "From good to great developer - why does it matters and how can we achieve it" by Chris Hedgate. Unfortunately, the recording only displayed the screen and not him and since the presentation relied on the audience being able to see him, I had to find another recoring. Luckily, I found pretty much the same presentation from JFokus, and this time they included Chris as well, success. See the movie here.

So, it was my turn to pick a video for our weekly developer lunch. I am not generally a fan of technical videos, but sometimes you find great ones.

This one however was really worth my time. An Introduction to Microsoft F# by Luca Bolognese, Microsoft's answer to Cristian Libardo. Competently and with a great sense of humor, he guides you through the basics of F# and proceeds to create a real world application for those still doubting the power and usefulness of F#.

A common misconception is that functional programming languages are strange, hard to learn and overly mathematical. This is very far from the truth. As Luca points out in the video, F# is much closer to how you actually think about a problem. I will not repeat what he is saying in the video - just make one hour free and watch it!

An Introduction to Microsoft F#
Microsoft F# Developer Center
Luca Bolognese's WebLog

My turn to select video for our developer lunch. And ofc i had to pick something about the SOLID principles as im a huge fan of atleast knowing how to keep your code nice and clean (I do a less than good job at practicing it though =) Do as i say, dont do as i do).

If you already are familiar with SOLID these clips wont give you much info and can probably stop reading now. But if you are new to it they give a nice overview of the basics, and what it means in code.

For people new to SOLID each letter stands for a principle. S is the Single responsibility principle, O is the Open/Closed principle, L is the Liskov substitution principle, I is the Interface segregation principle and D is the Dependency inversion principle. Each of the 5 movies will give you info on one of these principles.

Creating SOLID Code: Single Responsibility Principle (SRP)

Creating SOLID Code: Open/Closed Principle (OCP)

Creating SOLID Code: Liskov Substitution Principle

Creating SOLID Code: Interface Segregation Principle

Creating SOLID Code: Dependency Inversion Principle

Extra: This movie wasnt planned to be showed during the lunch, but its kinda nice aswell so i added it. They use the project created in the 5 first movies and show how easy adding dependency injection becomes if you are using these principles.

Creating SOLID Code: Refactoring the SOLID episode on DI to use StructureMap

This seminar lunch we went inspirational. Recently there has been a lot of talk about all the problems the web brings to the table. Issues around security and integrity are discussed frequently. Is it really that bad?

Jontahan Zittrain shows us in this inspirational video that the internet is a wonderful thing that inspires in it self. Thank you Jonathan for this great video!

While looking for interesting things to show I found quite a few interesting videos. Unfortunately almost all of them were way too long. I ended up with a video about C# 4.0 and the Dynamic Language Runtime (DLR). If I had watched the video before showing it I would have noticed that it lacked any kind of demonstrations, but in the end I found it interesting.

C# 4.0 Dynamic with Chris Burrows and Sam Ng

Here are a few links to browse through if interested, and of course, searching for "C# DLR" in your favorite search provider will provide you with lots of more information and samples.
Dynamic Language Runtime Overview
Using Type dynamic (C# Programming Guide)
CodePlex Page for Dynamic Language Runtime

Today at the premiere of our developer lunch I decided to share this presentation of Jack Moffitts JavaScript library, Strophe, from the 2009 JS Conf. In this video Jack explains XMPP (eXtensible Messaging and Presence Protocol), BOSH (Bidirectional-streams Over Synchronous HTTP) and gives a quick overview of the Strophe library. I think this is an exciting technique that we will see more and more on the web.

Watch the video at the JSConf website

More info on XMPP
More info on BOSH
More info on Strophe

Sites using the Strophe library:

Speeqe
Chesspark
Drop.io

Starting today, every thursday will be seminar lunch at Dropit. Each week one developer will be in charge of selecting a recorded seminar about something they really like. It could be anything from a presentation of C# 4 to JQuery to an discussion about BDD.

Each seminar will also be presented here at the blog by the person who picked it, so that you can be inspired too :-)