Re: If not Ada, what else...

[Peter C. Chapin <PChapin@vtc.vsc.edu>]

On Fri, 22 Apr 2011 10:49:41 -0700 (PDT), Brad Cantrell
<cantrellb@gmail.com> wrote:

>If you really want to compare Ada with functional languages, you
>should try Erlang. The promise of functional languages are in non-
>mutable variables and functions with no side effects which qualifies a
>language as being a "pure functional" language. Erlang is almost a
>subset of Haskell, the only difference is that its dynamically typed.
>It relies on pattern matching with guards much as Haskell does. But
>what sets Erlang apart from Haskell is that threading is built into
>the language so that it has practical value in dealing with the
>outside world.

Erlang is cool but I have to put in a pitch for Scala here. Scala comes
with an "actors" library that is modeled after Erlang's approach to
concurrency (message passing). However, like Ada, Scala is statically
typed.

The upcoming 2.9 release of Scala will also include parallel collections
that can be iterated over with parallel for loops (and, in fact, support
many other parallelized operations). This is accomplished without adding
any syntax to the language. Scala's native syntax is extensible enough as
is. For example:

// This method operates on a sequence of type T.
def someMethod[T](data: Seq[T]) = {
   for (item <- data par) {
     // Parallelized loop. Iterations are spread over multiple cores.
   }
}

In the above code 'par' is actually a method being applied to 'data.' The
for loop ends up being parallelized not because the compiler treats it in a
special way, but rather because of the behavior of the 'par' method.

Peter