Re: ADA Popularity Discussion Request

["Richard Riehle" <adaworks@earthlink.net>]

"Kevin Cline" <kevin.cline@gmail.com> wrote in message
news:e749549b.0408171554.2f9c48b4@posting.google.com...
>
> I don't your guru got it quite right.  Ada failed because most
> programmers who tried it found Ada programming to be relative less
> productive than programming in other available languages.  Ada never
> attracted a large enough base of motivated users to develop the
> libraries and IDEs that would make it easy to use.
>
I wonder why you think Ada is less productive than other
available languages.   Is it the static typing?  Is the ability
to define one's own types?   Is it the syntax?  Is it the way
the ALRM is written?

Over the years, I have come to the conclusion that a key
problem with Ada, in those early days, was that few of
those involved in teaching it really understood it well
enough to make it clear to those who needed to use it.

There are a few simple underlying ideas in the language. One
of them is type safety, and that has never been beyond the
comprehension of any programmer.   The idea that seems to
have been difficult to grasp, even by many who consider themselves
sophisticated software developers, is the separation of scope
and visibility.   Chapter Eight of the ALRM is rarely read by
anyone, it seems.

I recall being at a conference some years ago where someone
was giving a tutorial involving Ada.  At one point I suggested
changing a part of the design to a limited private type.  The
response, from a member of the technical staff of a well-known
compiler publisher, "Oh.  We don't design with limited because
you can't do anything with a limited type."

During nearly twenty years with Ada, I find that more programmers
have more trouble with the visibility rules than any other single
aspect of the language.   Sometimes, I as see a person struggling
to overcome those rules, I am reminded of the time during high
school when I took a part-time janitorial job and had to learn
to use a floor buffer.

Anyone who has ever had the experience of a circular floor
buffer will know what I am describing.   As soon as you take
hold of the handle, the buffer goes where it chooses, and no
amount of human muscle will overpower it.   In fact, the more
one tries to control it with brute force, the more it drags you
around the room.

Eventually, after nearly wrecking the furniture, I discovered that
I could take control of the buffer by lightly adjusting its position
relative to the floor.   In time, I learned to show off by moving
the buffer wherever I wanted, using one finger.   Instead of
fighting the design of the buffer, I learned to accomodate
myself to it.

Those who had the most difficulty with Ada, and those who
continue to have difficulty with it, are often trying to force
the language to do things the old way.   They are unable to
learn how a light touch, using the features of the language,
will make one more productive, not less productive.

I currently teach Ada in an academic environment.   My students
are in graduate school and very bright.   Many of them have
written programs in other languages.   When they first encounter
Ada, they too want to approach it the way they did other
languages.   After a short time, they learn the simple ideas behind
the design of the language and they learn to like it (most of them).
In fact, many like it far better than C++, Java, or many of the
other options they have been taught.

The benefits of the visibility rules needs to be given emphasis.  Those
rules are among the most powerful benefits of Ada, even though
some programmers continue to see them as a nuisance.

Richard Riehle