Thank you all, particularly Guido, for your contributions. Having some examples will help support the exploration of this idea. Here's a baby example - searching in a nested loop. Suppose we're looking for the word 'apple' in a collection of books. Once we've found it, we stop. for book in books: for page in book: if 'apple' in page: break if break: break However, suppose we say that we only look at the first 5000 or so words in each book. (We suppose a page is a list of words.) This leads to the following code. for book in books: word_count = 0 for page in book: word_count += len(page) if word in page: break if word_count >= 5000: break found if break found: break At this time, I'd like us to focus on examples of existing code, and semantics that might be helpful. I think once we have this, the discussion of syntax will be easier. By the way, the word_count example is as I typed it, but it has a typo. Did you spot it when you read it? (I only noticed it when re-reading my message.) Finally, thank you for your contributions. More examples please. -- Jonathan