ceph/src/boost/libs/container/example/doc_custom_small_vector.cpp

   1 //////////////////////////////////////////////////////////////////////////////
   2 //
   3 // (C) Copyright Ion Gaztanaga 2013-2013. Distributed under the Boost
   4 // Software License, Version 1.0. (See accompanying file
   5 // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // See http://www.boost.org/libs/container for documentation.
   8 //
   9 //////////////////////////////////////////////////////////////////////////////
  10 //[doc_custom_small_vector
  11 #include <boost/container/small_vector.hpp>
  12 #include <boost/static_assert.hpp>
  13
  14 //Make sure assertions are active
  15 #ifdef NDEBUG
  16 #undef NDEBUG
  17 #endif
  18 #include <cassert>
  19
  20 int main ()
  21 {
  22    using namespace boost::container;
  23
  24    //This option specifies the desired alignment for the internal value_type
  25    typedef small_vector_options< inplace_alignment<16u> >::type alignment_16_option_t;
  26
  27    //Check 16 byte alignment option
  28    small_vector<int, 10, void, alignment_16_option_t > sv;
  29    assert(((std::size_t)sv.data() % 16u) == 0);
  30
  31
  32    //This option specifies that a vector will increase its capacity 50%
  33    //each time the previous capacity was exhausted.
  34    typedef small_vector_options< growth_factor<growth_factor_50> >::type growth_50_option_t;
  35
  36    //Fill the vector until full capacity is reached
  37    small_vector<int, 10, void, growth_50_option_t > growth_50_vector(10, 0);
  38    const std::size_t old_cap = growth_50_vector.capacity();
  39    growth_50_vector.resize(old_cap);
  40
  41    //Now insert an additional item and check the new buffer is 50% bigger
  42    growth_50_vector.push_back(1);
  43    assert(growth_50_vector.capacity() == old_cap*3/2);
  44
  45    return 0;
  46 }
  47 //]