Is breaking out of io.lines(file) safe?

[mitchell <code@...>]

I want to iterate over the lines in a file, but break out if a certain 
condition is true. The documentation says the EOF is detected and the file 
is closed. If I break before the EOF is detected, is the file not closed? 
I don't want to leave open file references in my Lua state.

for line in io.lines(filename) do
  if condition then break end
  ...
end

Thanks,
mitchell