At 01:00 PM 2/3/2007, Cosmin Prund wrote: >The statement "And I do so without setting up unnecessary exception >handling which is, I expect, much more expensive than several IS tests" >makes it look like exception handling is something expensive and it >should be avoided. It's not, and it should be used as often as possible.
Yes, exception handling should be encouraged. However, sometimes developers use exceptions to trap and process conditions that are expected to occur in the normal course of operations and this should be avoided. So, you need to be judicious. For example, when translating a user-entered string into a numeric value. In those cases the developer can reasonably expect the user to enter a non-numeric at some point. You might be tempted, therefore, to trap the translation error with an exception and process the "error" that way. However, there have been considerable argument about whether this is correct and proper use of the exception mechanism. Some would argue that exception handling code should ONLY be used for conditions that cannot be anticipated in the normal course of operations. The above example would NOT qualify in this regard. Others would argue that exception handling should be used everywhere it works, without regard for the frequency of the exception occurrences. They think that even if a condition can normally occur 50% of the time it is OK to use the exception mechanism to perform what is essentially an if-test in the logic of the program. I agree with the former position and abhor the use of exception handling to control normal logic flow in the program. _______________________________________________ Delphi mailing list -> [email protected] http://www.elists.org/mailman/listinfo/delphi
