The Less Interesting TimesWhen Knowledge and Technology Invade

2014/04/24 Fun With LINQ Expressions, Lambda Functions and Ternary Operators

At work, we work with Unity. Unity comes with its own IDE, MonoDevelop.

MonoDevelop sucks. I hate the way it looks. I hate the way it folds code. I hate the way it unfolds everything every time you save. I like the way it finds files and classes but that’s about the only thing I like about it. And I have to use it for debugging.

However, I don’t have to use it for actual coding. I use Visual Studio 2013 because we already have it and it’s a pretty good tool. It does lack some advanced capabilities and so I installed the ReSharper plugin which adds a lot of power to VS and makes it even much more useful.

What I like about ReSharper is that it suggested a lot of improvements to my code and actually taught me more about LINQ expssions and Lamda functions. I already knew and much liked Ternary operators. I think that all of them make code more lean and prettier and easier to read as it makes it more legible in actual English.

The C Trenary operator is “?”. You use it like this: “(condition) ? (variable if true) : (variable if false)”. Much easier than “if (condition) then return variable1 else return variable2”.

Lambda functions are a kind of anonymous function that is much easier and shorter to write. So, instead of writing “delegate(KeyValuePair<long, string> pair) { do something with pair }” and shoving all that into a callback, you just write “pair => do something with pair”. It doesn’t look like a big improvement but it is in the long run.

LINQ expssions are a sort of C# extensions that provide more functionality to a lot of data structures in a way that make them very generic and very easy to understand.

Which brings me to my example of how I used all of them together to get a very powerful operation done in what is, technically, a single line of code that is also easy to read. Code has been obfuscated to protect the innocent.

List<AClass> AClassList = AListOfStringListPairs.Select(stringListPair => stringListPair.Key != specificKey ? stringListPair.Value.First() : null).ToList();

In English, notice the translation isn’t difficult, I take a List of pairs, where each pair is a string and a list of classes, and filter out the heads of every list whose string fulfill my required predicate and put those into a new list which I can later use.

With out LINQ or Lambda, at least, this code would have been 3-4 times longer if not more. So I like this a lot. There is only one problem: Because of an unavoidable constraint of our development method, we can’t use some specific collection method which LINQ uses almost all of the time. So I can’t use most LINQ expssions. Which sucks.

But not as much as MonoDevelop.

Posted in No Category, Practice, Programming, Thinking Out Loud, Work by Eran with 2 comments.