Demystifying Monads

remember that even if you are working for ThoughtWorks you should have a clue about what you are talking about and you should take some time to prepare presentations.

Or any other maintream language (C#, C++). F# is really not mainstream and looks like APL to me. Because of this the examples were useless and the presentation lost much of its interest.

This presentation should be considered harmful. You will end up being more confused than when you started, and it makes many incorrect or misleading statements. I vote that it be removed from InfoQ.

Actually, you can't represent the the general monad type in Java; the type system isn't rich enough to do so. You need higher-kinded types to express the monadic type.

In Scala, the monadic type looks like this:

trait Monad[M[_]] {
  def pure[A](a: A): M[A]
  def bind[A, X](m: M[A], f: A => M[X]): M[X] //aka return, aka >>=, aka flatMap...
}

interface Monad<A> {
  public <X> Monad<X> bind(F<A, Monad<X>> function);
}

interface Maybe<A> {
  public <X> Maybe<X> bind(F<A, Maybe<X>> function);
}

oops, that "//aka return" was supposed to be up a line

From your explanation a Java programmer already gets a better intuitive feel about the concept. I think that for something like this one should not refrain from "adding" the needed features to a language. If you need to be able to pass function around just add this missing feature to Java for the sake of the presentation. Explain the syntax you will use and then proceed with the explanation. Of course this can work only if the parts that are missing are few. If you need to add too much to the language then it becomes useless.
Thank you for your input.

Beautiful language and patterns he's *trying* to explain but he's like a zombie trying to talk about vegetarianism. Kick this asshole out and read this Simon Peyton-Jones paper: research.microsoft.com/en-us/um/people/simonpj/... .

Do you have a personal vendetta with this presenter? Where did you learn to communicate? Regardless of what you think of the presentation and presenter, it is you sir who comes across as the $%#hole. Let me guess, you are an American on East or West Coast? I would bet East...

Get some manners. You come across like a child.

Sorry.

I tend to overreact when Haskell is being misrepresented. And no, I'm not an American. And yes, in this particular one, I looked like a child. Your reply helped me to put myself in perspective.

Thanks, and sorry again.