Question

this seems to not be possible with dart? i.e. to have a class method recurse and eventually return an object? when i run a recursive method it invariably returns null IF it has recursed at least once…

example:

// some class method
rock throw_rock() {
  // look at its own collection of rocks
  // get a rock and do a test on it
  rock to_throw = this.rocks[53]; // lets assume its in a map at key 53...
  if (to_throw.been_thrown == 1) {
    // ok, dont throw this one, instead recurse and find another
    this.throw_rock();
  } else {
     return to_throw;
  }
}

in some other class or in main:

rock g = rock_thower.throw_rock();
// if rock thrower has had to recurse
// g will be null...

I am VERY new to dart and am not sure why that happens. Any ideas? Is this sane?

If not: what am I doing wrong?

Answer 1

It would need to be return this.throw_rock().

Which is to say, you want to return either your to_throw variable, or the result of the recursive call.