Arduino Compiling Issue with LinkedList

[placebo3681]

Hi there. Using your library for state machines in an Arduino project and ran into an issue with the following error. I do have the latest LinkedList version available through the Arduino library. Unless perhaps I installed incorrectly?

In file included from C:\Users\Daniel\Documents\Arduino\libraries\StateMachine\src\State.h:1:0,
from C:\Users\Daniel\Documents\Arduino\libraries\StateMachine\src\State.cpp:1:
C:\Users\Daniel\Documents\Arduino\libraries\LinkedList/LinkedList.h: In instantiation of 'ListNode* LinkedList::getNode(int) [with T = Transition*]':
C:\Users\Daniel\Documents\Arduino\libraries\LinkedList/LinkedList.h:314:28: required from 'T LinkedList::get(int) [with T = Transition*]'
C:\Users\Daniel\Documents\Arduino\libraries\StateMachine\src\State.cpp:46:32: required from here
C:\Users\Daniel\Documents\Arduino\libraries\LinkedList/LinkedList.h:160:9: error: cannot convert 'bool' to 'ListNode<Transition*>' in return
return false;
^~~~~
In file included from C:\Users\Daniel\Documents\Arduino\libraries\StateMachine\src\StateMachine.h:1:0,
from C:\Users\Daniel\Documents\Arduino\libraries\StateMachine\src\StateMachine.cpp:1:
C:\Users\Daniel\Documents\Arduino\libraries\LinkedList/LinkedList.h: In instantiation of 'ListNode LinkedList::getNode(int) [with T = State*]':
C:\Users\Daniel\Documents\Arduino\libraries\LinkedList/LinkedList.h:314:28: required from 'T LinkedList::get(int) [with T = State*]'
C:\Users\Daniel\Documents\Arduino\libraries\StateMachine\src\StateMachine.cpp:31:41: required from here
C:\Users\Daniel\Documents\Arduino\libraries\LinkedList/LinkedList.h:160:9: error: cannot convert 'bool' to 'ListNode<State*>*' in return
return false;
^~~~~
exit status 1
Error compiling for board Arduino Uno.

[mfresia]

Hi, I confirm the Issue.

I'm using Arduino 1.8.13 on Linux

same error messages.

I resolved changing line 160 of LinkedList.h library version: 1.2.3

from: return false;
to: return nullptr;

Now It compile.

[OlivierBourdin]

Hi @mfresia
Thank you very much for the fix. I had the same issue with Andrdoid 1.8.13 under Windows. I implemented your fix and now it works for me as well!

[atoav]

I have the same issue also with 1.8.13 (but on Linux). Adding the suggested change to line 160 of LinkedList version 1.2.3 didn't work for me:

Using library StateMachine at version 1.0.13 in folder: /home/myusername/Arduino/libraries/StateMachine 
Using library LinkedList at version 1.2.3 in folder: /home/myusername/Arduino/libraries/LinkedList 
exit status 1
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
cannot convert 'bool' to 'ListNode<Transition*>*' in return

[mccartes]

This fails to compile on arduino because the linked list library includes the following in a "tests.cpp" file:

#include
std::cout<< "Tests pass"<< std::endl;

I am not that experienced but it does not appear that iostream is supported with Arduino.
when I comment out these two lines, then the whole thing compiles successfully

However, then the serial monitor does not work. You need to delete the tests.cpp file in order for the serial monitor to work.