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From: kilgallen@eisner.decus.org (Larry Kilgallen)
Subject: Re: Ada vs C++ vs Java
Date: 1999/01/14
Message-ID: <1999Jan14.153651.1@eisner>#1/1
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 comp.lang.ada,comp.lang.c++,comp.realtime,comp.arch.embedded,comp.object,comp.lang.java.programmer
Date: 1999-01-14T00:00:00+00:00
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In article <P4qn2.4877$TO5.139567@ptah.visi.com>, "Erik Funkenbusch" <erikf@visi.com> writes:

> Which doesn't change the point that "safe" languages do not allow some
> things which are necessary to do certain things.  For instance, you can't
> use Java to point to a memory mapped I/O structure.  C++ can (because it
> allows pointers).

But the goal, presumably, is not to "point to" a memory mapped
I/O structure but rather to transfer data to and from it.

If Java does not allow that, it is certainly not because it is
impossible in a "safe" language, since Address Clauses in Ada
(even Ada83) allow you to define an entity (an array of 16-bit
words, for example) and specify its address.  Then you can
iterate through your array (or access specific elements in
your record, if you have chosen a non-uniform representation)
without running off the end as you might if you were programming
in a pointer-centric language.

Larry Kilgallen