1///////////////////////////////////////////////////////////////////////////////
2// count.hpp
3//
4// Copyright 2005 Eric Niebler. Distributed under the Boost
5// Software License, Version 1.0. (See accompanying file
6// LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
7
8#ifndef BOOST_ACCUMULATORS_STATISTICS_COUNT_HPP_EAN_28_10_2005
9#define BOOST_ACCUMULATORS_STATISTICS_COUNT_HPP_EAN_28_10_2005
10
11#include <boost/mpl/always.hpp>
12#include <boost/accumulators/framework/accumulator_base.hpp>
13#include <boost/accumulators/framework/extractor.hpp>
14#include <boost/accumulators/framework/depends_on.hpp>
15#include <boost/accumulators/statistics_fwd.hpp>
16
17namespace boost { namespace accumulators
18{
19
20namespace impl
21{
22
23 ///////////////////////////////////////////////////////////////////////////////
24 // count_impl
25 struct count_impl
26 : accumulator_base
27 {
28 // for boost::result_of
29 typedef std::size_t result_type;
30
31 count_impl(dont_care)
32 : cnt(0)
33 {
34 }
35
36 void operator ()(dont_care)
37 {
38 ++this->cnt;
39 }
40
41 result_type result(dont_care) const
42 {
43 return this->cnt;
44 }
45
46 private:
47 std::size_t cnt;
48 };
49
50} // namespace impl
51
52///////////////////////////////////////////////////////////////////////////////
53// tag::count
54//
55namespace tag
56{
57 struct count
58 : depends_on<>
59 {
60 /// INTERNAL ONLY
61 ///
62 typedef mpl::always<accumulators::impl::count_impl> impl;
63 };
64}
65
66///////////////////////////////////////////////////////////////////////////////
67// extract::count
68//
69namespace extract
70{
71 extractor<tag::count> const count = {};
72
73 BOOST_ACCUMULATORS_IGNORE_GLOBAL(count)
74}
75
76using extract::count;
77
78}} // namespace boost::accumulators
79
80#endif
81

source code of boost/boost/accumulators/statistics/count.hpp