The Real World: Powerful Functions

Lon Barfield

Imagine that you have a thousand monkeys sitting behind a thousand computer keyboards and that you set them tapping at random at the letters. It is said that if they carry on doing this day in day out eventually, after many years, one of them will just happen to type out the entire works of Shakespeare. It is also said that if you leave them tapping away for just six months then more than one of them will write a buggy, but marketable computer operating system.

Imagine how much faster it would be if the keyboards they were working on had one key mapped to a macro that produced all the ASCII for the complete works of Shakespeare; a real powerful function. After lining all the monkeys up you would only have to set them going for about five minutes before one of them hit the button and the task was complete.

Nowadays more and more technical systems are being equipped with these sort of powerful functions; one button that carries out a complete task. While this may be useful for meeting literary deadlines with a thousand monkeys, it does have disadvantages when it comes to error robustness. On any technological system a button can be pressed by accident by the user, by another party or just by being poked by something else in your rucksack. The effect of such an accidental poke is governed by the power of the function. The more powerful the function, the more serious the result.

At home I often let my two-year-old play with our, rather outdated, dial telephone, safe in the knowledge that no matter how much she pokes and prods the chances that she will dial the chinese speaking clock and then leave the telephone off the hook are astronomically small. However, when I am on the 'phone I keep well away from her since the button for hanging up then becomes a powerful function, a simple poke can result in the interruption of the entire conversation.

While we are on the subject of telephones there is the fascinating `dial M for Murder' story reported in the press a while back. A woman answers a phone call at home and hears, not a voice, but obvious sounds of a struggle. Then she hears a scream and realises that it is her daughter screaming. Suddenly the phone goes dead leaving the mother in a state of shock. Is her daughter being kidnapped, or has she disturbed a violent intruder in the flat? Her fears are confirmed when the 'phone goes again and she hears the same struggle going on and her daughter's voice shouting `Oh my God'. This time the mother hangs up and immediately alerts the police. When the police enter the daughter's flat they are met by a very embarrassed daughter and her boy friend and it emerges that in the frantic throes of their lovemaking someone knocked the receiver off the phone causing the `last number redial' button to be pressed. A simple accident, but serious results due to the power of the function under the button.

So, power functions incorporate efficiency, but the downside is that they cause problems if activated in error. The negative aspects of powerful functions do not just involve accidental usage. Some powerful functions have bad side-effects from everyday use. Consider the `copy file' function. In days gone by when everything was written by pen and typewriter, the concept of a back-up copy didn't really exist. I remember the advert in a student magazine in Manchester:

Stolen from the physics department car park: one light blue Ford Fiesta. You can keep the car but please return the Doctoral thesis that was on the back seat, it's my only copy and I have to submit next month!

Nowadays, with the powerful copy/duplicate commands, creating a copy is simply a menu option away. Many editors make backup copies automatically. The result is that if you are paranoid about computer crashes (as every computer user should be!) then your hard disk, the hard disk at home, the local hard disk and the email box of the place where you used to work and still have an account are full of different versions of the same document. You make copies as easily as breathing. You want someone to proofread it; you make a copy for them, you want to change the layout; you make a copy, convert it to ASCII; you make a copy. The result is a stagnant file system full of redundant copies where finding the last one that you worked on is as difficult as trying to trace a stolen Ford Fiesta.

Power functions also play a role in creative applications. Consider cameras with built in exposure programs and sets of filters. The glitzy results are easy to achieve, but the problem is that the results look as if they have been achieved simply by using the right combination of filters. This observation is also true but to a lesser extent for the Photoshop artwork software. In the creative world power functions once again make the difficult easier, but here the downside is that they can limit the creativity.

Computers have many more keys to be poked than a telephone and software is far more complex than a phone system thus amplifying the above problems. Among the many software benchmarks is a little know test for software stability called `the open book test'. You install the software, set it running and then open a large, heavy book and rest it on the keyboard as though to read it...

Lon Barfield

Lon Barfield is the author of `The User Interface, Concepts and Design' (Addison Wesley) and is an associate director of General Design (http://www.design.nl). He can be contacted at lon@design.nl.

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Vol.29 No.2, April 1997
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