It's been a while since I blogged a "pet peeve", and I know you're all anxiously awaiting the next entry in the series.

When you see code like this, run like mad!

try
  DoSomething;
except
end;

Note: You can have the same bad code in C#, and other languages, too.

The problem with this code is that you are swallowing ALL exceptions in this code block. For example, you now won't be notified of Access Violations, Out of Memory conditions, Invalid Pointer operations, or other system-level problems. If DoSomething is throwing an exception of a known type, handle it in the except block explicitly. If you don't know what exceptions can come back, don't handle them. It's really that simple. You can't count on your program working correctly from this point forward if you use this type of construct.

Now, I can think of some very rare places where you need this type of logic (e.g. if an exception leaks out, it will crash a poorly written host process, like IIS and ISAPI). But even then, it would be best to at least log the error somewhere (e.g. file, EventLog, whatever).

I'm almost done writing a very exhaustive paper on exception handling that I titled "Hitch Hiker's Guide To Exceptions". With any luck, I'll publish it to BDN. Stay tuned, and I'll certainly blog about that when/if it gets submitted and accepted.