Scor­pio News

tell there are a number of different pages, they are coloured differently. This leads to the most appalling Technicolour splodge on the screen – confusing, messy and not in the least helpful. Isn’t it simpler to use a larger area of screen – like all of it – for instructions and menus, and when done with them make them go away ? My preference is to use the whole screen for menus, offering all the choices at once with separate help screens (also full screen size) which come and go on request. It’s not first impressions which count. Windows (as pop-ups are called) might look very clever to the prospective buyer, but pity the person who has to use them with no other choice. After a day or so, they know the commands and what the help says. How they wish they could turn it all off.

Pop-up and pull-down menus are good in their place, like the mice, with graphics, but aren’t clever when it comes to anything which is predominately keyboard oriented. When someone is really familiar with something, menus and help screens aren’t required at all. So the step beyond my idea of full page menus is to make command keys work direct. You simply bash a key and the software goes ahead and does what is asked. Mind you, in keeping with the KISS idea of doing things, this last approach has to be pretty clever in its own right. The user might bash keys and the software reacts, but what if the wrong keys are hit ? This is a process known as ‘input validation’ and that’s what KISS is all about. Keep the software simple to use, but make the software check everything before it does it. This isn’t so easy as it sounds, because the software writer has to anticipate everything which could go wrong. I reckon a full 30% of the software I’ve written using these ideas is down to input validation.

Input validation must always be polite and to the point, in fact all responses from the computer must be polite and to the point. Users don’t like being insulted by a dumb machine, they don’t like their mistakes pointed out to them at any time, and least of all by a smart-arse computer. The error messages I see on a lot of software make me wince. These are terse in the extreme, and although not exactly rude, are not exactly helpful either. May be you’ve seen the sort of thing I mean:

“INPUT ERROR IN FIND.”

much nicer and more helpful to say

“You have entered the find command incorrectly, please correct and retry.”

A lot more words, but words costs nothing and at least it’s helpful, it tells you what you’ve done wrong and what to do about it. A few error messages like the first, and those who have little experience soon build up a resentment of the computer and will then use them reluctantly from then on. Some while ago, I got fed-up with writing polite software and wrote a cataloguing program where all the error messages were abusive to put it mildly and where it wasn’t abusive, it was wildly