B4J Question For Each as map in list Not Working?

MrKim · May 31, 2021

I have been using the same technique without issues for a while, now suddenly it is not working on one particular data set.
Dim LL As List = req.DBResultToMap(res) sets the map
I added this line for testing and as you can see the first Map is there:

But when I step to the next line I get my map is not initialized:

To be clear Dim Crsr As Map = LL.Get(0) was added only as a test because the the For Each was failing.
I have used this technique a dozen times before in this project and the others all work fine.
The only difference I can see is the data returned contains some large(for me) strings with a lot of CRLFs as you an see in the first shot.

Any ideas greatly appreciated.

MichalK73 · May 31, 2021

Check.

B4X:

for i = 0 to LL.Size-1
    dim Crsr as map = LL.get(i)
next

Erel · May 31, 2021

Please post the code and the logs.

MrKim · Jun 9, 2021

I'm sorry, I know I started the response to this but evidently it never got posted. Once again the failure was mine. It was a misspelling on my part.
HOWEVER
This is still an interesting issue. I was led down the wrong path because the Map shows as not initialized.
I have included a program that demonstrates the issue. B4X Pages, but only tested in b4J.

Dim Crsr As Map = LL.Get(0) Works:

For Each Crsr As Map In LL Shows as not initialized, however it DOES work (When you don't misspell the field name?).

Jorge M A · Jun 11, 2021

Maybe... ?

Tim Chapman said:
It means that the map is empty.

?

MrKim · Jun 12, 2021

Jorge M A said:
Maybe... ?

?

But it isn't. That is my point. The map still works

agraham · Jun 12, 2021

It does look like a bug in the Debug code. It seems to think Crsr is always one behind what it actually is. Step round the loop and you will see what I mean
First pass is empty, second pass is what should be the first and so on. I can't see a reason for this in the generated code - not surprisingly as, like you say, it works! Possibly because Crsr is a loop variable and debug is assuming it is somehow different. If you do the following and break after the Log then M displays as expected but Crsr doesn't.

B4X:

            For Each Crsr As Map In LL
                M = Crsr
                Log(Crsr.Get("Ra_CmdName"))

MrKim · Jun 13, 2021

agraham said:
It does look like a bug in the Debug code. It seems to think Crsr is always one behind what it actually is. Step round the loop and you will see what I mean
First pass is empty, second pass is what should be the first and so on. I can't see a reason for this in the generated code - not surprisingly as, like you say, it works! Possibly because Crsr is a loop variable and debug is assuming it is somehow different. If you do the following and break after the Log then M displays as expected but Crsr doesn't.

B4X:

For Each Crsr As Map In LL M = Crsr Log(Crsr.Get("Ra_CmdName"))

Thanks for taking a look. As I mentioned in post 4 it is not really an issue for me since it works. When I see an anomaly I like to post them even if I have a workaround primarily because I have no idea if it is a symptom of something bigger that might need to be looked at.

agraham · Jun 13, 2021

MrKim said:
When I see an anomaly I like to post them even if I have a workaround primarily because I have no idea if it is a symptom of something bigger that might need to be looked at.

Quite right too! In this case I do think it might be regarded as a bug so I have posted it as such.

Erel · Jun 13, 2021

This is indeed a bug in the debugger. It is related to the sub being a resumable sub.

B4J Question For Each as map in list Not Working?

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