Android Question equality and inequality operators with b4a long type

[b4xfr]

Dim along As Long = 40000000000000100
Dim along2 As Long = 40000000000000000
	
		If (along = along) Then
			Log("along is equal to itself")
		else
			Log("along is not equal to itself")
		End If
		
	
		If (along2 = along2) Then
			Log("along2 is equal to itself")
		else
			Log("along2 is not equal to itself")
		End If

this code output :
along is not equal to itself
along2 is equal to itself

I don't understand what is my mistake. If someone can explain me, thank you very much.

 

[Star-Dust]

Simple, buy a new device, I've tried your code on an old Android 4.0 and it works perfectly

** Service (starter) Create **
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
along is equal to itself
along2 is equal to itself
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = false **

 

[stevel05]

I copied and pasted your code into a new project and it gives the expected results.

 

[klaus]

I tried it too, works as expected.

 

[lemonisdead]

Inequality confirmed on Lenovo K6 (Android 7.0) and Equality on K10000 (Android 6). Si it really depends on the device

 

[b4xfr]

thank you very much for a so fast answer.
I use a real device and android 7.0 for testing. The problem could be that i use VirtualBox. I will investigate more.

 

[b4xfr]

Inequality confirmed on Lenovo K6 (Android 7.0) and Equality on K10000 (Android 6). Si it really depends on the device

Thank you very much. It help a lot. So apparently the problem is not related with my installation

 

[b4xfr]

I have tested the code in release mode. And it work as expected. So the problem appears only in debug mode.

Dim along As Long = 40000000000000100
     Dim along2 As Long = 40000000000000000
   
     If (along = along) Then
       ToastMessageShow("along is equal to itself",False)
       Log("along is equal to itself")
     Else
       ToastMessageShow("along is not equal to itself",False)
       Log("along is not equal to itself")
     End If
     
   
     If (along2 = along2) Then
       ToastMessageShow("along2 is equal to itself",False)
       Log("along2 is equal to itself")
     Else
       ToastMessageShow("along2 is not equal to itself", False)
       Log("along2 is not equal to itself")
     End If

 

[JordiCP]

It appears only in rapid debug (not legacy) mode, not in Activity_Create, when comparing local vars (not if they are globally declared), and only if they differ in the latest digits

So it "could seem" as if the comparison block logic was performed not with the numbers themselves but with their string representation, but only taking into account up to a given length?
Just a guess

EDIT:
After doing a "Project Clean" it works ok

 

[b4xfr]

@JordiCP. Thank you for these precisions.

After doing a "Project Clean" it works ok

The "project clean" worked for me too! (Why?)

 

[JordiCP]

As a rule of thumb, you can do it (clean project) as a check if you see "strange(r) things"
With legacy debugger it doesn't happen, but it's not as fast as the rapid debugger

 

[b4xfr]

With legacy debugger it doesn't happen, but it's not as fast as the rapid debugger

In fact I have only one debug mode. I don't know how to activate the "legacy debugger".

I will avoid if (a=b) and use preferably if (a-b=0), if (a-b)<>0, it worked before i made a "clean project".

 

[lemonisdead]

Tools \ IDE Options \ Use legacy debugger

 

[DonManfred]

You can find the legacy (Deprecated) Debugger in the Menu

 

[b4xfr]

Ha, thank you very much, here is the legacy debugger .

 

[Erel]

There is indeed a bug here. It happens in some cases in rapid debug mode (default debugger).

The rapid debugger has two pipelines. One is fast and static and the other is slower and more dynamic / sophisticated. This is why it can be tricky to reproduce it.

It can be reproduced with:

Dim along As Long = 40000000000000100
Log(along = along)
Log("put breakpoint here")

I guess that it is related to a conversion between double to long.

I recommend you to keep using the rapid debugger. You can put this code in a different sub. It will run properly as long as you don't modify the code. Clean the project if you do modify it to force a full compilation.

 

[b4xfr]

Ok.
Thank you very much. Indeed i can see that with the break point there is a latency before a log appear (with a false result) in the console.

The following code works well. In my point of view, this code will acces the value of the long and compute a difference, and my ancient code behaves as if it tested two different objects. A long versus a Long.

Dim along As Long = 40000000000000100
   Log(along - along = 0)
   Log("put breakpoint here")