Mark Storer [mailto:mstorer@cardiff.com] wrote:

If Boost's source were a closed book, and the only option was to throw an exception, then so be it. But that is not the case. On that note, I'm going to bring this thread back to discussion of how to use the current Boost library.

Using the Boost library as it currently stands, it appears the best way to abort the algorithm is to throw an exception. Whether or not throwing an exception is acceptable from a general programming standpoint is a topic more suited to a general C++ discussion list (if anyone decides to take it there, let me know - I'd like to follow it). Whether or not to add a return value to the BGL is a topic more suited to the main Boost mailing list. -- Jim