Object is not iterable

Question

Here is the error I get:

Traceback (most recent call last):
  File "C:\Users\Mendel Hornbacher\My programs\Spaceblaster\SpaceBlaster0.0.2b.py", line 95, in <module>
    animate()
  File "C:\Users\Mendel Hornbacher\My programs\Spaceblaster\SpaceBlaster0.0.2b.py", line 53, in animate
    ship.hit(astroid_list)
  File "C:\Users\Mendel Hornbacher\My programs\Spaceblaster\SpaceBlaster0.0.2b.py", line 34, in hit
    if pygame.sprite.spritecollide(self, item, False):
  File "C:\Python33\lib\site-packages\pygame\sprite.py", line 1515, in spritecollide
    return [s for s in group if spritecollide(s.rect)]
TypeError: 'Astroid' object is not iterable

and these are the classes involved:

animate:

def animate():
    ship.hit(astroid_list)
    ship.move()
    screen.fill([0,0,0])
    astroid_list.draw(screen)
    screen.blit(ship.image, ship.rect)
    pygame.display.flip()

self.hit (in 'Ship' class)

def hit(self, group):
        for item in group:
            group.remove(item)
            if pygame.sprite.spritecollide(self, item, False):
                self.die()
            group.add(item)

astroid_list
```
astroid_list = pygame.sprite.Group()
```

If it means anything I'm running windows 8 pro. If the above code is not enough I'll post the whole code in a comment.

But you would be able to edit more information into the question (See the edit link) — David Robinson, Dec 21 '12 at 18:50
You shouldn't be trying to remove objects while iterating through them at the same time. — Diego Allen, Dec 21 '12 at 18:56

score 2 · Answer 1 · answered Dec 21 '12 at 18:54

You are passing a single sprite to spritecollide when it expects to get a list of sprites. This is causing the exception to be thrown because your Astroid is not a iterable class.

def hit(self, group):
    if pygame.sprite.spritecollide(self, group, False):
        self.die()

Spritecollide documentation

Nice little tip from the documentation is that pygame.sprite.spritecollideany is slightly faster then the regular spritecollide and would be probably a better choice since you do not care what you collided with it appears, so you do not need to return what you have collided with.

Martijn Pieters · Accepted Answer · 2012-12-21T19:00:48.427

The spritecollide function expects you to pass a Group, not individual sprites.

Just test with your whole group in one go:

def hit(self, group):
    if pygame.sprite.spritecollide(self, group, False):
        self.die()

Now you also avoid removing and adding items to a list while looping over it.

If you want to remove the sprites self collides with from the group, do so after calling spritecollide():

def hit(self, group):
    collided = pygame.sprite.spritecollide(self, group, False)
    for item in collided:
        group.remove(item)
    if collided:
        self.die()

Instead of manually removing each item though, you could just set the dokill flag to True, and they will be removed from the group for you:

def hit(self, group):
    if pygame.sprite.spritecollide(self, group, True):
        self.die()

If you do not need to know what items collided and do not want to remove items from the group, use spritecollideany() instead; it returns just True or False and is faster:

def hit(self, group):
    if pygame.sprite.spritecollideany(self, group):
        self.die()

Object is not iterable

2 Answers2