Splitting strings - by iterators?

[Jeremy Sanders]

I have a large string containing lines of text separated by '\n'. I'm
currently using text.splitlines(True) to break the text into lines, and
I'm iterating over the resulting list.

This is very slow (when using 400000 lines!). Other than dumping the
string to a file, and reading it back using the file iterator, is there a
way to quickly iterate over the lines?

I tried using newpos=text.find('\n', pos), and returning the chopped text
text[pos:newpos+1], but this is much slower than splitlines.

Any ideas?

Thanks

Jeremy