Expression Language Misunderstanding: indexOf()

Ignition
1

I have the following Expression Structure:

{
"Valves":[
0:Open
1:Closed
2:Closed
...
]

I want to return true if any of the valves are open

When I do the following:

{value}["Valves"][0] = "Open"

Result: true

When I do the following:

indexOf({value}["Valves"],"Open")

Result: -1

Can someone explain what I am doing wrong or what assumptions I have that are incorrect? I also tried checking the typeOf({value}["Valves"][0] and it is a string...

2

{value}["Valves"] is not {value}["Valves"][0].

indexOf() does not find the index of a string in a list, it finds the index of a substring in a string.

What are you trying to accomplish?

3

I would use my Toolkit's where() iterator, wrapped in len(). Like so:

len(
    where(
        {value}['Valves'],
        it() = 'Open'
    )
) > 0

(I would also collapse your expression structure to use my asList() and nest it directly in the final expression. Avoid the transform overhead.)

4

Oh duh, that makes sense. I am looking for if any of the values are "Open" then I want to return True

5

Is a native clean solution not available?

6

No. My Toolkit closes many gaps in the native expression language, especially when dealing with lists, maps, and variable-length objects.

7

I'm bummed that there is no clean native solution. I am going to install your module to test it out, but I am unable to do a gateway restart at this time so I cannot test it out. Thank You for your work on this module.

8

Probably the best you can get in a single binding without Phil's module, is to add a script transform.

return any(valve == 'Open' for valve in value)

Phil's module is worth it, you will not know what you did without it.

9

:blush:

(Worth the bureaucratic trouble, if any, only, as it is free.)

10

am I missing something? I tried to recreate your issue and was unable to.

I created a property:

{
"valves":
[
"open",
"closed",
"closed"
]
}

I created a binding to that and ran this expression:

indexOf({value}['valves'], 'open')

it returns 0 and when I remove the string open from the list it returns -1, which is the intended result for what you described

this should natively work if you just need to check if it is contained in the list and not how many

11

I think the list behavior was added recently. @paul-griffith would know.

12

I don't think it's that recent because according to the 8.1 documentation indexOf | Ignition User Manual it says that it can take a list or tuple and it shows that documentation was last updated jan 13, 2025.

13

Interesting. "As of version 8.1.8". That was quite a while ago. Maybe there's a nuance/bug to expression structure bindings?

14

Yeah, it's expression structure bindings.

Most other contexts, if you're dealing with a list of values, it's a QualifiedValue over a list.
Expression structure bindings chained into a transform, for whatever reason, are a QualifiedValue containing a list of qualified values.
The indexOf function implementation unpacks the right hand side 'needle' into "Open", but doesn't touch the lhs/haystack, so the index checking doesn't work.

We already have code to unpack arrays of nested qualified values, we just need to add a branch for lists.

15

Ah. Run it through my unQualify() function.