gnubol: For your amusement

["William M. Klein" <wmklein@ix.netcom.com>]

For your amusement (especially for those "pondering" the future of OO and
especially OO COBOL) - from a post on the comp.lang.cobol newsgroup

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I received the following from a man that 'hates'  OO. I think it's fun
  ...

Once upon a time, in a kingdom not far from here, a king summoned two of his
advisors for a test. He showed them both a shiny metal box with
two slots in the top, a control knob, and a lever. "What do you think
this is?" One advisor, an Electrical Engineer, answered first. "It is a
toaster," he said.

The king asked, "How would you design an embedded computer for it?"

The advisor, "Using a four-bit microcontroller, I would write a simple
program that reads the darkness knob and quantifies its position to one of 16
shades of darkness, from snow white to coal black. The program would use that
darkness level as the index to a 16-element table of initial timer values.
Then it would turn on the heating elements and start the timer with the
initial value selected from the table. At the end of the time delay, it would
turn off the heat and pop up the toast.

Come back next week, and I'll show you a working prototype."

The second advisor, a software developer, immediately recognized the
danger of such short-sighted thinking. He said, "Toasters don't just
turn bread into toast, they are also used to warm frozen waffles. What
you see before you is really a breakfast food cooker. As the subjects of your
kingdom become more sophisticated, they will demand more
capabilities. They will need a breakfast food cooker that can also cook
sausage, fry bacon, and make scrambled eggs.

A toaster that only makes toast will soon be obsolete. If we don't look to
the future, we will have to completely redesign the toaster in just a few
years."

"With this in mind, we can formulate a more intelligent solution to the
problem. First, create a class of breakfast foods. Specialize this class into
subclasses: grains, pork, and poultry. The specialization process should be
repeated with grains divided into toast, muffins, pancakes, and waffles; pork
divided into sausage, links, and bacon; and poultry divided into scrambled
eggs, hard-boiled eggs, poached eggs, fried eggs, and various omelet
classes."

"The ham and cheese omelet class is worth special attention because it must
inherit characteristics from the pork, dairy, and poultry classes.

Thus, we see that the problem cannot be properly solved without multiple
inheritance. At run time, the program must create the proper object and send
a message to the object that says, 'Cook yourself.' The semantics of this
message depend, of course, on the kind of object, so they have a different
meaning to a piece of toast than to scrambled eggs."

"Reviewing the process so far, we see that the analysis phase has
revealed that the primary requirement is to cook any kind of breakfast
food. In the design phase, we have discovered some derived requirements.

Specifically, we need an object-oriented language with multiple
inheritance. Of course, users don't want the eggs to get cold while the bacon
is frying, so concurrent processing is required, too."

"We must not forget the user interface. The lever that lowers the food
lacks versatility, and the darkness knob is confusing. Users won't buy
the product unless it has a user-friendly, graphical interface. When the
breakfast cooker is plugged in, users should see a cowboy boot on the screen.
Users click on it, and the message 'Booting UNIX v.8.3' appears on the
screen. (UNIX 8.3 should be out by the time the product gets to the market.)
Users can pull down a menu and click on the foods they want to cook."

"Having made the wise decision of specifying the software first in the
design phase, all that remains is to pick an adequate hardware platform for
the implementation phase. An Intel Pentium with 48MB of memory, a 1.2GB hard
disk, and a SVGA monitor should be sufficient. If you select a multitasking,
object oriented language that supports multiple inheritance and has a
built-in GUI, writing the program will be a snap."

The king wisely had the software developer beheaded, and they all lived
happily ever after.

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