“Robert, in all due respect, I think your time would be better spent convincing C# or Java programmers to give functional programming a try than to waste energy in such internecine wars. Given enough determination and superficial knowledge anyone can come up with horrid code in any language. So what?” – Martin Odersky

I thought it was sad when Tim O’Reilly turned up on my blog trying to tell me how to sell books when our business was booming and he was laying off workers but seeing Martin Odersky here really takes the biscuit. Why would C# programmers care about Scala when it also lacks tail calls, decent type inference and algebraic datatypes (let alone inferred ones like OCaml’s polymorphic variants)?

“And OCaml? OObscurity. Is it aiming to be the new Perl 6? It’s already there.
Please, if you’re going to soapbox OCaml, post some great success stories other than wink.com.” – ToddC

I try to keep a list of OCaml’s biggest industrial success stories here but it just keeps growing (e.g. MLState just shipped their first OCaml product):

http://www.ffconsultancy.com/products/ocaml_journal/free/introduction.html

Perhaps the biggest is Microsoft’s imminent productization of a closely related language (F#). No sign of that happening to Scala. Indeed, Scala will be lucky to get tail calls before Sun disappear forever.

To make a real life code base, say a bank’s 10000 classes or more, take lots of ignorant code-typers, a few average engineers, some of them clever. The result is very much ugly/horrible/terrific code, academically unmaintainble, and very few clever ideas always half-way.

The real life code base just works (thousands of happy and unhappy customers).

The real point about real life programming is that very different people can join around a programming language/patterns/idioms/frameworks/versions and they can interpret partially each other’s code, and expand it.

Experimented people learn to guide less skilled coders in order to improve the code base. Both learn, both grow up.

Language purity is just as sterile as trying to have everybody think and act the same way.

The PhD professor writing a beautiful higher-order function is right as long as his findings are useful to someone else.
The stupid coder who programs using Ctrl-Tab code-completion is also right as long as the bank’s customers can get the bank’s services.

So your arguments about being functional or not are futile.

In everyday world you do not choose the people you work with and you do not choose the existing code base. You enter into a flow of always evolving code and people, and you have to help others to evolve from the existing code base in a way THEY can make sense of it.

You could help functional language ignorants like me explaining me what is worth in that paradigm and when I have to look at OOP.

As far as I can see, Scala is a mix that provides a bridge between two worlds, where mixing them seems to provide more than keeping structured-and-OO java-based approach. I would like to understand how functional programming could help me to maintain and improve the real life 10000 classes maintained by very different clever persons.