[Sigia-l] Error Prevantion Heuristic (slightly OT)

[Listera]

"Richard_Dalton at VANGUARD.COM" wrote:

> This is a slightly rhetorical question because I know you'd never do that - so
> I guess my question is "why?" - what heuristic or principle of "good design"
> is overriding the "prevent errors" one in this instance?

It depends on the context.

If this field entry is a (very) occasional task, entry-followed-by-alert may
be acceptable. If, however, it's a repeated task (done, for example, by data
entry operators), it won't be acceptable to have to dismiss alert boxes
continuously within the workflow.

Strictly speaking, you are not actually *preventing* the user from pressing
the '6' key, you're post-processing it to divert it to either an alert or,
what's essentially, a 'clear keystroke'.

'Preventing' would be three separate popup choice lists for each digit, with
the first one containing only 1,2,3,4,5.

'Rules' without context are meant to annoy people who care.

Ziya
Nullius in Verba