Clear error VI inserted in error wire on LV2009 code

[george seifert]

I converted a VI from LV8.6 to LV2009. There is a ClearError VI inserted in the error wire (see attached). Why did it do that?

No my code isn't this ugly. I used the new create snippet to create the png file and it uglied it up a bit.

George

[Aristos Queue]

I converted a VI from LV8.6 to LV2009. There is a ClearError VI inserted in the error wire (see attached). Why did it do that?

No my code isn't this ugly. I used the new create snippet to create the png file and it uglied it up a bit.

George

1. Ourcode conventions say that when we insert something like that on yourdiagram, you should see a load warning when you load the VI explainingthe change. Did you get such a warning? If not, please file a CAR.
2. Generallythis would be done for any node that used to silently fail some caseand in the new version it returns an error code for that case. Existingcode may have been written to assume the silent failure. To preserveprevious version functionality, we insert a function to conditionallyclear the new error code.
3. Inserting a full "Clear Errors.vi"that wipes out all error information would be strange... The only caseI can imagine that applying to is if in the previous version the nodeutterly failed to propagate error in to error out and we have fixedthat, but, again, to preserve previous functionality, we clear allerrors downstream. But that's just a guess. [LATER] Looking closer atyour posted picture, that is just a conditional clearing of the errorcode, so I'll bet #2 applies.

[george seifert]

1. Ourcode conventions say that when we insert something like that on yourdiagram, you should see a load warning when you load the VI explainingthe change. Did you get such a warning? If not, please file a CAR.
2. Generallythis would be done for any node that used to silently fail some caseand in the new version it returns an error code for that case. Existingcode may have been written to assume the silent failure. To preserveprevious version functionality, we insert a function to conditionallyclear the new error code.
3. Inserting a full "Clear Errors.vi"that wipes out all error information would be strange... The only caseI can imagine that applying to is if in the previous version the nodeutterly failed to propagate error in to error out and we have fixedthat, but, again, to preserve previous functionality, we clear allerrors downstream. But that's just a guess. [LATER] Looking closer atyour posted picture, that is just a conditional clearing of the errorcode, so I'll bet #2 applies.

Actually I didn't look too carefully at the list of changes it made. There were so many other changes due to code that I moved around that I didn't bother to look. Lesson learned there.

Yes, it did just insert a clear error for the one error code. So I guess LV did everything correctly. I just saw that weird VI inserted in my code and didn't know why it got put there.

George