Showing results for 
Search instead for 
Did you mean: 

Remove the stacked sequence structure from LabVIEW.

Remove once and for all the stacked sequence structure from labVIEW


                                       It's an absolute horror.




0 Kudos
Message 1 of 195

There are (rare) scenarios where a stacked sequence is appropriate. The main problem are sequence locals.

0 Kudos
Message 2 of 195

Thats like saying "Remove Globals and Locals."  It really makes no sense.  Sure, the SSS, like Globals and Locals, can be abused.  And, unfortunatly often is!  But, it does provide a syntatactic element in LabVIEW that serves a unique purpose.  


You could argue that you can always code around the lack by choosing a state machine.   LabVIEW 1 and 2 did not have Globals!  you can code around them!  Performance improvements were made possible by their introduction.


I'll make you a deal!  I'll Kudos the idea if you provide a benchmark of a SSS and a SM with IDENTICAL functionality (including MUST complete and in an exact inveriable order) where performance is not impacted.  You might surprise me.

"Should be" isn't "Is" -Jay
0 Kudos
Message 3 of 195

" ... it does provide a syntactic element in LabVIEW that serves a unique purpose"

and what is this "unique purpose"?

Is this purpose so important to justify the use of an architecture as bad as the Stacked Sequence ?


" ... where performance is not impacted"

Does the performance justify the use of everything and anything?


(sorry for my bad English, I do my best, thank you)

0 Kudos
Message 4 of 195
Sequence locals are sometimes (for very few cases) usefull if you know how to use them properly. I like to use stacked sequences to initialize and terminate my VIs (controls/indicators/arrays/etc..). Using stacked sequences to do tasks in a specific order without connection between each other can is OK in my opinion (saves BD space and is easy to understand). Using them for operational functions (communication process, acquisition, calculation, data export) is not the right usecase for it. In fact, the stacked sequence is only usefull if you know how to use it properly. There is of couse always the alternative of a state-machine or something similar, but the overhead is to much in my opinion (unless you have a state-machine anyways). So for me, the question is not if this function is necessary, neither if it is used by anybody, but rather if the developer knows how to do their job properly. You want people to not use it? Try to convince people instead of removing a tool from my toolkit just because someone does not know when and how to use it.
0 Kudos
Message 5 of 195

> Sequence locals are sometimes (for very few cases) usefull if you know how to use them properly


What does that even mean????


(.. and you are repeating basically the same statement about four more times as if  the use of sequences and sequence locals is an advanced skill, only to be used by LabVIEW masters. Your post is so redundant that it could be condensed to 20% of the size without loss of information).


It is clear that the stacked sequence can never disappear from LabVIEW, because of the need for backward compatibility. (It could be taken out of the palette, but why...).

0 Kudos
Message 6 of 195

@altenbach : "it is clear that the stacked sequence can never disappear from LabVIEW, because of the need for backward compatibility."


I understand, but's unfortunate to keep bad things "indefinitely" just for backward compatibility.

0 Kudos
Message 7 of 195

@altenbach: Sorry I repeated myself, should have read it a third time... However I don't think it's that redundant. My post states my way of using the structure and my opinion to one of their alternative. The last part is a bit harsh, but again my opinion (sorry if I offended you or anybody). There are more polite words to describe it I guess...


I don't think the structure is only for skilled LabVIEW masters as I don't think state-machines or for-loops are. Its the developer who has to decide when to use which tool, based on his knowledge and experience. Would be sad to have a tool removed just because it is used the wrong way (whatever the wrong way is).


To your question: I make use of sequence locals on very few occasions where initial data is produced in the first sequence and used in any following (could easily be replaced by tunnels...). There is no other need to it for me (anymore I must say).

0 Kudos
Message 8 of 195

I love SSS arguments, uh, umm I mean "discussions". Smiley Very Happy


The SSS is useful. It should stay. The sequence locals, however are an Obamanation. Smiley Surprised


If shift registers were added to the SSS I would find them extremely useful.


LabVIEW versions 5.0 - 2020

“All programmers are optimists”
― Frederick P. Brooks Jr.
0 Kudos
Message 9 of 195

@PaulG: The sequence locals, however are an abomination.

we agree, the sequence locals are an absolute horror.


@PaulG: If shift registers were added to the SSS ...

an interesting idea ...this could restore my faith in the sss 😉

0 Kudos
Message 10 of 195