Skip to main content

Anonymous types and functions in Visual Basic.Net

A lot of people poo poo VB.NET and yet I think almost none of them know anything about it. It has essentially all the same functionality as C#. With the latest versions of VB.NET you can use anonymous functions really nicely. I think the syntax is very clear and it makes it more obvious to a beginner programmer what is happening ie, the lambda you are passing into the where is a function. I think that's a real commendable thing to do and the syntax is very true to the language.

I think you would find an awful lot of C# developers using expressions such as

results.Where(x => x.Success);

but many of them (certainly a lot of the devs I have met in the past) would not really understand what is happening here. It's arguably not important but that's not fair. Using lambdas just in Linq wastes so much potential of the language.

Anyway, there's an example below in VB.NET. This syntax is in some ways more similar to the way F# does lambdas! ie

let test = fun x x < 2

Now if we can only convince them to make a binding like "let" that's immutable, we would really be cooking on gas!

Comments

Popular posts from this blog

An instantiated object should be "ok"

I've been QA'ing quite a bit of work recently and one common theme I've noticed across both Java and C# projects I have been looking at is that we occasionally open ourselves up unessacarily to Exceptions by the way objects are being created. My general rule of thumb (which I have seen mentioned in a Pluralsight video recently but also always re-iterate in various Robust Software talks I have done) is that you shouldn't be able to create an object and then call a method or access a property that then throws an exception. At worst, it should return null (I'm not going to moan about that now). I've created an example below. We have two Dojos, one is good and one is bad. The bad dojo looks very familiar though. It's a little class written in the style that seems often encouraged. In fact, many classes start life as something like this. Then as years go on, you and other colleagues add more features to the class and it's instantiation becomes a second

Accessing the UI Thread with Tasks in F#

I have a Windows Forms program written in F# that can deploy a code base to n number of sites at once (you select the sites you would like to deploy to and it goes off and completes a number of tasks (backing up current sites, various unpacking and moving of files etc... ). Once you start it, it begins it's merry journey and begins to update the UI with what has happened. At the moment this method of updating the UI is not pretty because the threads I am doing the work on can't update the UI so I perform some fiendery to make that happen (don't ask). I knew there was a better way using some newer .NET features but I just hadn't got round to having a fiddle yet. I have now found that if you use the built in Task class but break your code up in a nicer way and then chain the tasks together you can then pass the correct context into the task that you want to talk to the UI. Here's a little script to give you a feel for it. You can press the "start" butt

NESTA - Next Gen.

via nesta.org.uk Following on from an article on the BBC about Raspberry Pi, this next gen report has some interesting findings. The scariest stat which I picked out from the BBC website was "out of the 28,767 teachers who were awarded Qualified Teacher Status... in 2010, only three qualified in computing or computing science as their primary qualification" Having worked as a computer science teacher for a year in a school that was a specialist in Computing I can concur that the uptake in Comp Sci was woeful. 2 Students for A2... The other teachers backgrounds in Computer Science was also fairly woeful (most knowing a bit about Office but still a paltry amount even about that). I couldn't speak for my counterpart that I was covering however. I suspect they were fairly up on things. All in all what kills me is that Computer science is not a secondary level subject. Areas are often covered, a little in IT, a little in DT subjects (if kids choose Systems and Contr