Protothreading

Projects Programming
1

I'm looking into protothreading: Arduino Playground - TimedAction Library

I understand for

for (First; Last; increment)

do while, and while loops.

I don't understand part of this bracket (from the example in the link above)

void blink(){
  ledState ? ledState=false : ledState=true;
  digitalWrite(ledPin,ledState);
}

I don't understand the layout of ledState ? ledState=false : ledState=true;

2

Translation:

ledState is true?
If yes, set it to false
If no, set it to true

This statement inverts true to false or false to true. I would rather say ledState=!ledState; where the ! means NOT.

3

That's the ternary operator:

     boolean_value ? result_if_true : result_if_false;

They are using a round-about way of inverting the boolean value of ledState. The easy way is:

    ledState = ! ledState;

They could also have used the operator more properly:

     ledState = ledState ? false : true;
4

Thank you very much guys!
liudr & johnwasser
I understand now.

5

Xnor:
I don't understand the layout of ledState ? ledState=false : ledState=true;

Yeah, the person who coded that probably didn't understand it either. It's a misuse of the ternary operator and a very contrived way to invert a boolean.

6

Maybe?