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119 lines
3.2 KiB
C++
119 lines
3.2 KiB
C++
// -- control_structures.cpp -- The Boost Lambda Library ------------------
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//
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// Copyright (C) 2000-2003 Jaakko Järvi (jaakko.jarvi@cs.utu.fi)
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// Copyright (C) 2000-2003 Gary Powell (powellg@amazon.com)
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//
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// Permission to copy, use, sell and distribute this software is granted
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// provided this copyright notice appears in all copies.
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// Permission to modify the code and to distribute modified code is granted
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// provided this copyright notice appears in all copies, and a notice
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// that the code was modified is included with the copyright notice.
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//
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// This software is provided "as is" without express or implied warranty,
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// and with no claim as to its suitability for any purpose.
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//
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// For more information, see www.boost.org
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// -----------------------------------------------------------------------
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#define BOOST_INCLUDE_MAIN // for testing, include rather than link
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#include <boost/test/test_tools.hpp> // see "Header Implementation Option"
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#include "boost/lambda/lambda.hpp"
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#include "boost/lambda/if.hpp"
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#include "boost/lambda/loops.hpp"
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#include <iostream>
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#include <algorithm>
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#include <vector>
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using namespace boost;
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using namespace boost::lambda;
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// 2 container for_each
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template <class InputIter1, class InputIter2, class Function>
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Function for_each(InputIter1 first, InputIter1 last,
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InputIter2 first2, Function f) {
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for ( ; first != last; ++first, ++first2)
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f(*first, *first2);
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return f;
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}
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void simple_loops() {
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// for loops ---------------------------------------------------------
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int i;
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int arithmetic_series = 0;
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for_loop(_1 = 0, _1 < 10, _1++, arithmetic_series += _1)(i);
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BOOST_TEST(arithmetic_series == 45);
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// no body case
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for_loop(var(i) = 0, var(i) < 100, ++var(i))();
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BOOST_TEST(i == 100);
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// while loops -------------------------------------------------------
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int a = 0, b = 0, c = 0;
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while_loop((_1 + _2) >= (_1 * _2), (++_1, ++_2, ++_3))(a, b, c);
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BOOST_TEST(c == 3);
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int count;
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count = 0; i = 0;
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while_loop(_1++ < 10, ++var(count))(i);
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BOOST_TEST(count == 10);
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// note that the first parameter of do_while_loop is the condition
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count = 0; i = 0;
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do_while_loop(_1++ < 10, ++var(count))(i);
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BOOST_TEST(count == 11);
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a = 0;
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do_while_loop(constant(false), _1++)(a);
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BOOST_TEST(a == 1);
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// no body cases
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a = 40; b = 30;
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while_loop(--_1 > _2)(a, b);
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BOOST_TEST(a == b);
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// (the no body case for do_while_loop is pretty redundant)
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a = 40; b = 30;
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do_while_loop(--_1 > _2)(a, b);
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BOOST_TEST(a == b);
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}
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void simple_ifs () {
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int value = 42;
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if_then(_1 < 0, _1 = 0)(value);
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BOOST_TEST(value == 42);
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value = -42;
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if_then(_1 < 0, _1 = -_1)(value);
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BOOST_TEST(value == 42);
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int min;
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if_then_else(_1 < _2, var(min) = _1, var(min) = _2)
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(make_const(1), make_const(2));
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BOOST_TEST(min == 1);
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if_then_else(_1 < _2, var(min) = _1, var(min) = _2)
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(make_const(5), make_const(3));
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BOOST_TEST(min == 3);
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int x, y;
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x = -1; y = 1;
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BOOST_TEST(if_then_else_return(_1 < _2, _2, _1)(x, y) == std::max(x ,y));
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BOOST_TEST(if_then_else_return(_1 < _2, _2, _1)(y, x) == std::max(x ,y));
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}
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int test_main(int, char *[])
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{
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simple_loops();
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simple_ifs();
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return 0;
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}
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