[Boost-users] Help with a boost::lambda problem and boost::array?

Does anyone have an idea why the following doesn't compile: using lambda::_1; using lambda::_2; boost::function<double (const boost::array<double, 2>&)> f = lambda::ret<double>(_1[0] * _1[1]); But the following does as a double-check: using lambda::_1; using lambda::_2; boost::function<double (const double&, const double&)> f2 = lambda::ret<double>(_1 * _2); Thanks, Jesse