Can this code be made more Pythonic? Loops

Question

So I am writing some code to roll three fudge dice (six sided dice with sides of -1,-1,0,0,+1,+1). If the three dice together roll a total of -3, I have a function that then rolls a single fudge dice over and over again, subtacting 1 from the total for each -1 that get's rolled and quiting if something other than a -1 is rolled - in this way I get an "explosion down" making totals less than -3 possible, though increasingly less likely.

My explode down function is this:

def explodedown():
  curval = -3
  while 1:
    newroll = rolldie()
    if newroll != -1:
      break
    else:
      curval = curval-1
  return curval;

That seems to work well enough, but I almost feel that if I wanted to write this even more simply, there should be some way to write the loop more like:

while newroll == -1
  newroll = rolldie()
  curval = curval-1

And then the loop would naturally break without needing an if statement. Problem is newroll does not exist until we get inside the loop, so I don't think that will work. Maybe if I added another statement before the loop starts like:

newroll = rolldie()
while newroll == -1
  newroll = rolldie()
  curval = curval-1

But it seems un-pythonic to have the newroll line there twice.

Thoughts? is there a way to simplify and make more readable my explode down function?

Answer 1

You could do it like this:

while rolldie() == -1:
    curval -= 1