Returns whether any key of the structure is true-valued.The keys of the structure must be Logicals. If the structure is not finite, a true-valued key must appear at a finite "index" in order for this method to finish. More...
Louis Dionne 2013-2016 Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
