> Functional programming isn’t an afterthought in C#, it’s effective and you should learn it if you haven’t already.

I think C# is the best functional programming language because you always have access to a procedural code safety valve if the situation calls for it.

100% purity down the entire vertical is a very strong anti-pattern. You want to focus on putting the functional code where it is most likely to be wrong or cause trouble (your business logic). Worrying about making the underlying infrastructure functional is where I start to zone out.

Does F# care if a DLL it references was coded in a functional style?

If you're going to write code snippets, please make sure they compile!

The final example has signature List<Product> but tries to return IOrderedEnumerable<Product>.

I recognise that this is very much a taster rather than even a full introduction, so the author didn't want to explain IOrderedEnumerable<T>, but please when writing blogs, run through your code examples and make sure they compile.

This means that your audience can follow along.

( It just needs a .ToList() on the end. )