ceph/src/boost/libs/phoenix/test/bll_compatibility/control_structures.cpp

   1 // -- control_structures.cpp -- The Boost Lambda Library ------------------
   2 //
   3 // Copyright (C) 2000-2003 Jaakko Jarvi (jaakko.jarvi@cs.utu.fi)
   4 // Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
   5 //
   6 // Distributed under the Boost Software License, Version 1.0. (See
   7 // accompanying file LICENSE_1_0.txt or copy at
   8 // http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10 // For more information, see www.boost.org
  11
  12 // -----------------------------------------------------------------------
  13
  14 #include <boost/test/minimal.hpp>    // see "Header Implementation Option"
  15
  16 #include "boost/lambda/lambda.hpp"
  17 #include "boost/lambda/if.hpp"
  18 #include "boost/lambda/loops.hpp"
  19
  20 #include <iostream>
  21 #include <algorithm>
  22 #include <vector>
  23
  24 using namespace boost;
  25
  26 using boost::lambda::constant;
  27 using boost::lambda::_1;
  28 using boost::lambda::_2;
  29 using boost::lambda::_3;
  30 using boost::lambda::make_const;
  31 using boost::lambda::for_loop;
  32 using boost::lambda::while_loop;
  33 using boost::lambda::do_while_loop;
  34 using boost::lambda::if_then;
  35 using boost::lambda::if_then_else;
  36 using boost::lambda::if_then_else_return;
  37
  38 // 2 container for_each
  39 template <class InputIter1, class InputIter2, class Function>
  40 Function for_each(InputIter1 first, InputIter1 last,
  41                   InputIter2 first2, Function f) {
  42   for ( ; first != last; ++first, ++first2)
  43     f(*first, *first2);
  44   return f;
  45 }
  46
  47 void simple_loops() {
  48
  49   // for loops ---------------------------------------------------------
  50   int i;
  51   int arithmetic_series = 0;
  52   for_loop(_1 = 0, _1 < 10, _1++, arithmetic_series += _1)(i);
  53   BOOST_CHECK(arithmetic_series == 45);
  54
  55   // no body case
  56   for_loop(boost::lambda::var(i) = 0, boost::lambda::var(i) < 100, ++boost::lambda::var(i))();
  57   BOOST_CHECK(i == 100);
  58
  59   // while loops -------------------------------------------------------
  60   int a = 0, b = 0, c = 0;
  61
  62   while_loop((_1 + _2) >= (_1 * _2), (++_1, ++_2, ++_3))(a, b, c);
  63   BOOST_CHECK(c == 3);
  64
  65   int count;
  66   count = 0; i = 0;
  67   while_loop(_1++ < 10, ++boost::lambda::var(count))(i);
  68   BOOST_CHECK(count == 10);
  69
  70   // note that the first parameter of do_while_loop is the condition
  71   count = 0; i = 0;
  72   do_while_loop(_1++ < 10, ++boost::lambda::var(count))(i);
  73   BOOST_CHECK(count == 11);
  74
  75   a = 0;
  76   do_while_loop(constant(false), _1++)(a);
  77   BOOST_CHECK(a == 1);
  78
  79   // no body cases
  80   a = 40; b = 30;
  81   while_loop(--_1 > _2)(a, b);
  82   BOOST_CHECK(a == b);
  83
  84   // (the no body case for do_while_loop is pretty redundant)
  85   a = 40; b = 30;
  86   do_while_loop(--_1 > _2)(a, b);
  87   BOOST_CHECK(a == b);
  88
  89
  90 }
  91
  92 void simple_ifs () {
  93
  94   int value = 42;
  95   if_then(_1 < 0, _1 = 0)(value);
  96   BOOST_CHECK(value == 42);
  97
  98   value = -42;
  99   if_then(_1 < 0, _1 = -_1)(value);
 100   BOOST_CHECK(value == 42);
 101
 102   int min;
 103   if_then_else(_1 < _2, boost::lambda::var(min) = _1, boost::lambda::var(min) = _2)
 104      (make_const(1), make_const(2));
 105   BOOST_CHECK(min == 1);
 106
 107   if_then_else(_1 < _2, boost::lambda::var(min) = _1, boost::lambda::var(min) = _2)
 108      (make_const(5), make_const(3));
 109   BOOST_CHECK(min == 3);
 110
 111   int x, y;
 112   x = -1; y = 1;
 113   BOOST_CHECK(if_then_else_return(_1 < _2, _2, _1)(x, y) == (std::max)(x ,y));
 114   BOOST_CHECK(if_then_else_return(_1 < _2, _2, _1)(y, x) == (std::max)(x ,y));
 115 }
 116
 117
 118 int test_main(int, char *[])
 119 {
 120   simple_loops();
 121   simple_ifs();
 122   return 0;
 123 }