Scripting Challenge: Determine of a terminal is a Sequence Local

[littlesphaeroid]

While writing a plugin that deals with cluster terminals, I found that I needed to distinguish among terminals in various contexts: on control and indicator terminals, tunnels, and yes even sequence locals in stacked sequence structures--for completeness only.

In most cases I have been able to determine from a terminal's ownership hierarchy (accessed from the "Owner" property") what flavor of terminal I'm dealing with. But I found that this does not work for terminals inside of flat or stacked sequence structures. Any terminal inside a Sequence structure has an ownership hierarchy that looks like

[some object]:Diagram:Sequence:TopLevelDiagram

OR

[some object]:Diagram:FlatSequeceFrame:FlatSequence:TopLevelDiagram

Obviously there may be more levels to this for nested structures, but there's no hint of the sequence local here.

 

I have a workaround for my plugin, because I needed to make this distinction only for placement in a contextual menu, and I could use a particular menu items of a sequence local to determine the difference, but it seems like there should be another way, and relying on the menu seems too fragile in the face of version changes.

[billko]

I guess that's just one more reason to add to my list of reasons why stacked sequence structures are evil.  😉

[wiebe@CARYA · Accepted solution]

If the owner structure is a sequence, get it's list of it's locals (Sequence Locals[] property). From each sequence local, get a list of terminals. Keep that list.

For each terminal, see if it's in the list of sequence terminals. If there is a match (a Search 1D Array should work), the terminal is a sequence local...

It depends a bit on the context. Are you traversing controls, wires, structures? Perhaps you can post a VI that demonstrates the problem, so we can work on it?

[littlesphaeroid]

Your solution makes sense, and I'll try it out. I am acting on a right-clicked sequence local (or any other terminal). By using the owner reference, I can get the sequence locals of the sequence structure and determine of the clicked terminal is in that list. Great!

[littlesphaeroid]

I have attached sample code that shows how to determine if a terminal reference is a sequence local.