Re: Press Release - Ada 2012 Language Standard Approved by ISO

[Georg Bauhaus <rm.dash-bauhaus@futureapps.de>]

On 21.12.12 10:01, Dmitry A. Kazakov wrote:
> What I see is a yet another way to pack implementations into
> declarations as Georg promptly suggested, a slippery slope...

Operational aspects of definitions, and assignments---similar to
Adjust, Initialize, or Finalize---turn a static, flat plane of
non-operational definitions into something that a programmer can
work with, because it responds to his or her efforts at
definitions. The programmer is important here, not necessarily
the program, not yet.  At a stage when programmers have no
complete understanding of the program yet, as is usually the case
outside theaters, what means of programming are better than
nothing at all?

So, constraints, Dynamic_Predictes, may have one or two other uses.

The barium platino-cyanide paper on R�ntgen's workbench was just
an aspect, at run-time. It was not deliberately a part of his
programmed experiment. It turned into an important aspect though,
because it made R�ntgen notice something, at run-time.

"And what did you think?"

"I did not think; I investigated. I assumed that the effect must
  have come from the tube, since its character indicated that it
  could come from nowhere else. I tested it.  In a few minutes
  there was no doubt about it."

R�ntgen had not even planned for paper laying there. Yet, had the
black line across the paper not revealed an aspect, one for which
he did not have proper abstractions, he would not have found X rays.

It seems foolish to assume that, during program development,
we just follow perfect notions of what we have to do.
Two programmers sitting in the corner knowing everything
about the program they intend to write---only in a pipe dream.

Consequently, placing assumptions with definitions seems an
honest thing to do. It does not kill other ways of expressing our
knowledge. It does not require that we remove parts of a later
program once they become unnecessary.