mxcl/homebrew — pull request #15267 by repeatedly (2012-10-03 05:07:59+00:00)
Title: zookeeper: fomula always ignore --c option

'or' and '=' pair cause unexpected result in 'or' chain.

Behavior check code:
```ruby
a = nil
b = nil
c = 0
p a or b or c #=> nil - old code
p (a or b) or c #=> nil
p ((a or b) or c) #=> 0 - fixed code
```