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From: Michael Wojcik <mwojcik@newsguy.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: Call by Result
Date: Wed, 15 Jun 2011 21:33:15 -0400
Organization: Micro Focus
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Andreas Leitgeb wrote:
> 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.

They both get it from ML, which AFAIK is the first programming
language in that particular family. It introduced the type inference
and matching features that you find in OCaml (which is the OO version
of Caml, a ML dialect), Haskell, Scala, F# (which is basically OCaml
adapted for .NET), etc.

In the Verona of functional languages, the ML family are the Montagues
to the LISP family's Capulets. Or something like that.

-- 
Michael Wojcik
Micro Focus
Rhetoric & Writing, Michigan State University