Re: children

[Robb.Nebbe@di.epfl.ch (Robb Nebbe)]

In article <D68E9I.6DH@thomsoft.com>, kst@thomsoft.com (Keith Thompson) writes:
|> Mind you, I *like* child units, and I'm glad that Ada 95 has them.
|> I'm just suggesting that a little bit of theoretical security has been
|> lost relative to Ada 83; it's not surprising that a lot of people are
|> uncomfortable with that.

I am not surprised that people might initially react to the
perceived loss of security but once you have thought about it
I don't see how they can continue to worry about it.

My perspective is that child units substantially increase the
flexibility of the langauge. I want the language to protect me
from accidental mistakes and inconsistent models. I like the
fact that Ada makes me say what I mean but once I have said it
I don't want the language to second guess me I want it to
make sure I stick to it.

For me child units replace several uses of Unchecked_Conversion
and cases where I would have had to nest a package inside
another. If I would have put something in another package in
Ada83 I will not put it in a child package in Ada95. Of course
there is nothing in the language to stop me from doing this
but there is nothing in Ada83 to stop me from nesting a package
inside another either.

The need for a pragma to restrict unwanted children is really
no more important that a pragma to restrict unwanted nested
packages, which we seemed to do fine without in Ada83.

Robb Nebbe