59 lines
1.5 KiB
C++
59 lines
1.5 KiB
C++
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// Copyright (C) 2008-2018 Lorenzo Caminiti
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// Distributed under the Boost Software License, Version 1.0 (see accompanying
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// file LICENSE_1_0.txt or a copy at http://www.boost.org/LICENSE_1_0.txt).
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// See: http://www.boost.org/doc/libs/release/libs/contract/doc/html/index.html
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#include <boost/contract.hpp>
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#include <boost/type_traits/has_equal_to.hpp>
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#include <boost/bind.hpp>
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#include <vector>
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#include <functional>
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#include <cassert>
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//[condition_if
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template<typename T>
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class vector {
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public:
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void push_back(T const& value) {
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boost::contract::check c = boost::contract::public_function(this)
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.postcondition([&] {
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// Instead of `ASSERT(back() == value)` for T without `==`.
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BOOST_CONTRACT_ASSERT(
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boost::contract::condition_if<boost::has_equal_to<T> >(
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boost::bind(std::equal_to<T>(),
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boost::cref(back()),
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boost::cref(value)
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)
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)
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);
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})
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;
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vect_.push_back(value);
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}
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/* ... */
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//]
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T const& back() const { return vect_.back(); }
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private:
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std::vector<T> vect_;
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};
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int main() {
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vector<int> v;
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v.push_back(1); // Type `int` has `==` so check postcondition.
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assert(v.back() == 1);
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struct i { int value; } j;
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j.value = 10;
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vector<i> w;
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w.push_back(j); // Type `i` has no `==` so skip postcondition.
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assert(j.value == 10);
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return 0;
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}
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