hi,

just try a little bit but i doesnt work...

Code:

boolean value = true;
   print(value);

void mousePressed() {
  if(value == false) {
   print(value);
  } else {
   print(value);
  }
} 

why wont work this ? just want to change the status of value
thank u

it just gives me some error messages...

i dont get it why its wrong.

i just define a boolean.
then check if its true false, and print the status.

I think the issue is a little more complex: you can use print() in a simple 'static mode' sketch (i.e. one without setup and draw methods), but when any of these are included (or in fact mousePressed) you get the error.  I suspect the reason for this is the fact that the interpretor handles static sketches differently to those that include setup and draw (or other 'interactive' methods)...

Whilst 'static mode' is fine for very simple sketches to test basic functionality you're mostly going to be wanting things to happen, like registering mouse presses, and that requires a draw loop (mouse events are registered after each draw loop); which means including both setup and draw methods.  I'd suggest looking through the getting started section for clarification and some examples