Array elements crashing program [SOLVED]

[DomesticAnt]

I'm trying to write a simple path finding algorithm, and I've run into a problem with cbot arrays that I can't seem to work around:

I'm trying to create a 2d array representing the map at a 1m scale, so the array is nominally 808 by 808 elements.

If I try to initialize all the elements to some default value, Colobot GE slows to a crawl and I eventually have to kill the process.

Since Colobot appears to support sparse arrays, it seemed like a good idea to initialize only those array elements that the simple pathfinder actually needed to access (typically just a few hundred). The problem with THAT is that I can't find any way at all to test if an array element has been initialized.

Consider the following simple example program:

Code:

extern void object::artest()
{
    errmode(0); //This suppresses the "Variable not Initialized" error message, but doesn't stop the script from halting
    
    message( "Hello World" );
    int foo[]; // sizeof(foo) == 0
    
    foo[10] = 42; // sizeof(foo) == 11
    
    if( foo[0] == 0 ) {
        message( "This never happens" );
    }
    else {
        message( "This also never happens" );
    }
    
    message( "You won't see this message" );
}

So "sizeof(foo)" is no help.

"if( foo[0] == null )" fails to compile

EDIT:

While messing about with something unrelated, I stumbled upon a  solution using CBot's largely undocumented try-catch syntax. The following program seems to run as expected:

Code:

extern void object::artest()
{
  errmode(0); //This suppresses the "Variable not Initialized" error message, but doesn't stop the script from halting

  message( "Hello World" );
  int foo[]; // sizeof(foo) == 0

  foo[10] = 42; // sizeof(foo) == 11

  for( int i = 0; i < sizeof(foo); i++ ) {
    int v = SafeRead( foo, i );
    message( "foo[" + i + "] = " + v );
  }

  message( "Program finished" );
}

int object::SafeRead( int[] ar, int n ) {
    int defaultvalue = -99;
    int rv;
    
    try {
        rv = ar[n];
    }
    catch( CBotErrNotInit ) {
        message( "SafeRead() Caught Not-Initialized Error, returning default", DisplayError );
        return defaultvalue;
    }
    catch( CBotErrOutArray ) {
        message( "SafeRead() Caught Out-of-Bounds Error, returning default", DisplayError );
        return defaultvalue;
    }
    
    return rv;
}

My SafeRead() function isn't as generic as I'd like, but it should be trivial to adapt for use in most situations where something like this is needed.