Answering an old question that got lost in the fray ... Scott Woods wrote:
"What[ 0 ]" is the odd one out; it does not have an implicit mapping to a manifest sub-expression. To RE-philes (I think my first exposure to $0 was in "vi"?) it's de rigueur. To those C++ developers that were born more recently but are familiar with STL, it's a wrinkle. Does processing of "what" always involve "++what.begin()" only because "what.complete()" fails to compete with tradition.
I understand what you're saying, but I don't agree that it's that for solely for legacy reasons. In practice, the only reason why you might iterator over all sub-matches is to print them out. Otherwise, the sub-matches are accessed randomly, because (for example) the 1st sub-match is a date and the 3rd sub-match is an email address, and I'm not interested in the 2nd. See? -- Eric Niebler Boost Consulting www.boost-consulting.com