Documentation for the minmax library.

Moved from libs/minmax/ to libs/algorithm/minmax
Also changed documentation to reflect use of Boost.tuple
and separation into two header files. --Herve'


[SVN r23308]

minmax/test/minmax_test.cpp

@@ -0,0 +1,78 @@
+#include <utility>
+#include <functional>
+#include <algorithm>
+#include <numeric>
+#include <iterator>
+#include <vector>
+#include <list>
+#include <set>
+#include <iostream>
+
+#include <boost/algorithm/minmax.hpp>
+#include <boost/test/included/test_exec_monitor.hpp>
+
+class custom {
+  int _M_x;
+  friend bool operator<(custom const& x, custom const& y);
+  friend std::ostream& operator<<(std::ostream& str, custom const& x);
+public:
+  explicit custom(int x = 0) : _M_x(x) {}
+  custom(custom const& y) : _M_x(y._M_x) {}
+  custom operator+(custom const& y) const { return custom(_M_x+y._M_x); }
+  custom& operator+=(custom const& y) { _M_x += y._M_x; return *this; }
+};
+
+bool operator< (custom const& x, custom const& y)
+{
+  return x._M_x < y._M_x;
+}
+
+template <class Value>
+struct less_count : std::less<Value> {
+  typedef std::less<Value> Base;
+  less_count(less_count<Value> const& lc) : _M_counter(lc._M_counter) {}
+  less_count(int& counter) : _M_counter(counter) {}
+  bool operator()(Value const& a, Value const& b) const {
+    ++_M_counter;
+    return Base::operator()(a,b);
+  }
+  void reset() {
+    _M_counter = 0;
+  }
+private:
+  int& _M_counter;
+};
+
+template <class Value>
+void test(int n, char* name)
+{
+  using namespace boost;
+
+  // Test functionality
+  tuple<Value const&, Value const&> result = minmax(0, 1);
+  BOOST_CHECK_EQUAL( result.get<0>(), 0 );
+  BOOST_CHECK_EQUAL( result.get<1>(), 1 );
+
+  result = minmax(1, 0);
+  BOOST_CHECK_EQUAL( result.get<0>(), 0 );
+  BOOST_CHECK_EQUAL( result.get<1>(), 1 );
+  
+  // Test functionality and number of comparisons
+  int counter = 0;
+  BOOST_CHECK_EQUAL( result.get<0>(), 0 );
+  BOOST_CHECK_EQUAL( result.get<1>(), 1 );
+  BOOST_CHECK_EQUAL( counter, 1 );
+
+  result = minmax(1, 0, less_count<Value>(counter) );
+  BOOST_CHECK_EQUAL( result.get<0>(), 0 );
+  BOOST_CHECK_EQUAL( result.get<1>(), 1 );
+  BOOST_CHECK_EQUAL( counter, 2);
+}
+
+int test_main( int argc, char* argv[] )
+{
+  test<int>(n, "builtin");
+  test<custom>(n, "custom ");
+
+  return 0;
+}