Loop iterator - example.txt

[Dan]

>> In pseudo-code ...
>> 
>>    foreach (inout Customer cust; CustomerSet )
>>    {
>>        try {
>>        cust.name = UI.CustName;
>>        cust.address = UI.Address;
>>        . . .
>>        }
>>        catch (BadUI e)
>>        {
>>            // Recover from the (rare) UI data error
>>            . . .
>>            retry; // Reprocess the same customer record.
>>        }
>>    }
>> 
>
>Does that retry that instance, or retry the entire loop? Couldn't the 
>semantics be either, given the appropriate condition?

Fortunately, it's not ambiguous.  The try/catch is INSIDE the loop, so it will
continue the loop where it left off once the error is handled.  If the try/catch
were outside the loop, it would run the whole loop over again.

I don't think it's really that difficult; and no, you can't separate the
try/catch and have one in and one out.  That's a syntax error.  If you throw
errors and catch them elsewhere, my understanding is that the program *should*
resume at the end of the try block once it's handled.  Please correct me if I'm
wrong.

Also, unless some method is throwing an error, I highly recommend simply using
if or assert instead of try/catch.  I *think* try/catch is traditionally done
through a very time consuming system fault mechanism, whereas if/assert are
simply a "short jcc" instruction.