[Boost-users] Oven, regular and Boost

The 'Oven' port... http://dl.dropbox.com/u/1682460/git/OvenToBoost/libs/range/doc/html/range_ex... makes much of its 'regular' operator, which is used to fix this problem using boost::lambda::_1; for_each_(r | filtered(_1 % 2 == 0), f); // Error! Can't default construct/copy assign for_each_(r | filtered(regular(_1 % 2 == 0)), f); // OK However, AFAICS this is not a problem in current-ishBoost (1.47). Has this ever been a problem? Can anyone comment on its general provenance? Thx, Rob.