ceph/src/boost/libs/geometry/include/boost/geometry/algorithms/detail/check_iterator_range.hpp

   1 // Boost.Geometry (aka GGL, Generic Geometry Library)
   2
   3 // Copyright (c) 2014, Oracle and/or its affiliates.
   4
   5 // Contributed and/or modified by Menelaos Karavelas, on behalf of Oracle
   6
   7 // Licensed under the Boost Software License version 1.0.
   8 // http://www.boost.org/users/license.html
   9
  10 #ifndef BOOST_GEOMETRY_ALGORITHMS_DETAIL_CHECK_ITERATOR_RANGE_HPP
  11 #define BOOST_GEOMETRY_ALGORITHMS_DETAIL_CHECK_ITERATOR_RANGE_HPP
  12
  13 #include <boost/core/ignore_unused.hpp>
  14
  15
  16 namespace boost { namespace geometry
  17 {
  18
  19 #ifndef DOXYGEN_NO_DETAIL
  20 namespace detail
  21 {
  22
  23 // Check whether (each element of) an iterator range satisfies a given
  24 // predicate.
  25 // The predicate must be implemented as having a static apply unary
  26 // method that returns a bool.
  27 // By default an empty range is accepted
  28 template <typename Predicate, bool AllowEmptyRange = true>
  29 struct check_iterator_range
  30 {
  31     template <typename InputIterator>
  32     static inline bool apply(InputIterator first, InputIterator beyond)
  33     {
  34         for (InputIterator it = first; it != beyond; ++it)
  35         {
  36             if (! Predicate::apply(*it))
  37             {
  38                 return false;
  39             }
  40         }
  41         return AllowEmptyRange || first != beyond;
  42     }
  43
  44
  45     // version where we can pass a predicate object
  46     template <typename InputIterator>
  47     static inline bool apply(InputIterator first,
  48                              InputIterator beyond,
  49                              Predicate const& predicate)
  50     {
  51         // in case predicate's apply method is static, MSVC will
  52         // complain that predicate is not used
  53         boost::ignore_unused(predicate);
  54
  55         for (InputIterator it = first; it != beyond; ++it)
  56         {
  57             if (! predicate.apply(*it))
  58             {
  59                 return false;
  60             }
  61         }
  62         return AllowEmptyRange || first != beyond;
  63     }
  64 };
  65
  66 } // namespace detail
  67 #endif // DOXYGEN_NO_DETAIL
  68
  69 }} // namespace boost::geometry
  70
  71 #endif // BOOST_GEOMETRY_ALGORITHMS_DETAIL_CHECK_ITERATOR_RANGE_HPP