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From: Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at>
Subject: Re: Call by Result
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Date: 14 Jun 2011 10:52:41 GMT
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Silvio <silvio@moc.com> wrote:
> Well, here is an example in Scala:
>  [...]
> def getString(s : String) : Option[String] =
> {
>     if (s.reverse == s) Some(s.toLowerCase)
>     else None
> }
>  [...]
>  val t = getString(s)
>  [...]
> t match
> {
>     case Some(r) => println("Success, return value is: " + r)
>     case None => println("Failure")
> }

Ah, thanks.  Yep, I've seen this concept once when playing with 
OCaml (which mentions Haskell as one of its roots). Never got 
warm with it, though.

In the end, it isn't all that more concise than C++/Java...
It's a bit like C's unions with some byte ahead to tell which
of the variants is the current one, and bunch of logical operations
that is often trivially converted into a couple of (possibly nested)
"if-else"s.   I'm not saying it's bad, just it didn't impress me all
that much, so far.