Exception error when pulling from list after "split".

[kari_payton]

[ FlexSim 21.2.4 ]

exception error help.fsmI have a 3 sub-flows and in each sub-flow I pull a different item from a list. The first 2 sub-flows happen in parallel, and the 3rd sub-flow will happen after.

I'm trying to read labels from the items pulled from the list. I get an error when the sub-flow in red is placed after the join block.

exception: FlexScript exception: Retrieving travel_XLoc_tip label property on node that does not exist at MODEL:/Tools/ProcessFlow/Molding/Assign Object Location Labels>labels/1/2

If I put the red box before the split, I don't get any errors. However when placed after the split I get the above error. Any idea why?

[Matthew_Gillespie]

@Kari Payton Did you attach an older version of your model? I don't see the set of activities in the picture in the attached model.

[kari_payton]

@Matthew Gillespie sorry I attached the wrong images. I get the error on the model attached above and it's on this flow. When I reverse the order of "Run Sub Flow" and "Get 3rd Web" it works fine. Seems like when I pull items from the list, I lose the reference, although the items have different partition ID's.

[Matthew_Gillespie · Accepted solution]

The exception is being caused because the pulled token immediately goes to a Finish activity and is destroyed before the pulling token can get labels off of it. You should add a Breathe (Delay activity with a delay of 0) after the "Push to Ready for Web Assembly List List" activity to ensure that pulled tokens don't immediately get destroyed.

exception-error-help_1.fsm

It only works if you switch the order of the activities because it happens to change which token is waiting for the other. If "Get 3rd Web" is on top then the pulling token is waiting for the other token to be pushed, and once it is the puller moves first and gets the labels off the token it pulled before its destroyed. If "Get 3rd Web" is on bottom then the pushed token is waiting for the other token to pull it, and once its pulled the pushed token moves first and moves down to be destroyed before the pulling token can get the labels it wants.

Adding a breathe after the push will make sure either order works for getting labels off the pushed token.

[kari_payton]

thanks @Matthew Gillespie!