Re: Ada in teaching

["John B. Matthews" <nospam@nospam.invalid>]

In article <4a5d17f2$0$30231$9b4e6d93@newsspool1.arcor-online.net>,
 Georg Bauhaus <rm.tsoh.plus-bug.bauhaus@maps.futureapps.de> wrote:

> > John B. Matthews wrote:

[...]
> Java arrays cannot fully take advantage of Java generics, in 
> particular compile time checking is basically off, so the sloppy 
> base type system strikes again.

It's an unfortunate legacy.

> Another language corner case that I imagine must be explained
> to students of the (Java) language at length.

The usual explanation is that arrays are covariant, with 
type-checking enforced at runtime; Java generic types are 
invariant, checked only at compile-time [1].
 
> > and task oriented support for concurrent programming [2].
> 
> Yes, task *oriented*.

Indeed. I think Java's original support for concurrent programming was 
offered at much too low a level. Ada 83's level may have been a bit too 
high, with protected types, for example, added in Ada 95 and enhanced 
in Ada 2005 [3].

In both areas, type-checking and concurrent programming, I see Ada and 
Java moving in similar directions, if not actually converging.

I don't teach except in the sense of occasionally being asked to guide 
students of one language in using the other. I'd be interested to learn 
of any reference that outlines corresponding features of the two 
languages.

Students (or teachers) of both languages may like to look at these 
simple projects done in both Ada [4, 5] and Java [6, 7], respectively.

[...]

[1]<http://java.sun.com/docs/books/effective/generics.pdf>
[2]<http://java.sun.com/j2se/1.5.0/docs/api/java/util/concurrent/
package-summary.html>
[3]<http://www.adaic.com/standards/05rat/html/Rat-1-3-4.html>
[4]<http://home.roadrunner.com/~jbmatthews/misc/groots.html>
[5]<http://home.roadrunner.com/~jbmatthews/jumble.html>
[6]<http://sites.google.com/site/drjohnbmatthews/polyroots>
[7]<http://sites.google.com/site/drjohnbmatthews/jumble>

-- 
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>