errorDialog - how reliable?

Alex Rice alex at
Thu Oct 9 02:29:01 EDT 2003

On Thursday, October 9, 2003, at 12:11  AM, Richard Gaskin wrote:

>  And other times when lockErrorDialogs will catch nearly everything.

I thought lockErrorDialogs was supposed to prevent errorDialog messages 
from being sent. Then nothing is "caught" at all.

> FWIW, while a single _optimal_ solution has eluded me all these years, 
> I've
> found few errors that could not be trapped for and handled gracefully 
> one
> way or another.  That's why we love good testers....

Richard, I'm glad you are comfortable with the design choices you have 
made, and your tone is reassuring. I am not suggesting that throwing 
exceptions is a substitute for QA testing and design for usability. I 
am not suggesting that I would stop using Rev because of this issue.

But you are speaking in general terms and I really have a specific 
concern: How is it possible for errorDialog messages to vanish & how 
can I make sure it never happens in my built apps? I am still learning 
the best ways to think and code in transcript. Having programmed in 
Java I have a particular concept of how exception handling is supposed 
to work.

To quote Stroustrup on exception handling

"Successful fault-tolerant systems are multilevel. Each level copes 
with as many errors as it can without getting too contorted and leaves 
the rest to higher levels."

In my case "higher levels" means the IDE or the runtime engine. If the 
runtime tosses exceptions- errorDialog messages- into the great bit 
bucket where does that leave me? Back to square 1 and ready to rip 
every single throw statement out of my code.

Exceptions are for *very unusual situations*. Should very unusual 
situations be met with complete silence?


Alex Rice <alex at> | Mindlube Software |

what a waste of thumbs that are opposable
to make machines that are disposable  -Ani DiFranco

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