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// Copyright (C) 2008-2018 Lorenzo Caminiti
// Distributed under the Boost Software License, Version 1.0 (see accompanying
// file LICENSE_1_0.txt or a copy at http://www.boost.org/LICENSE_1_0.txt).
// See: http://www.boost.org/doc/libs/release/libs/contract/doc/html/index.html
#include <vector>
#include <limits>
#include <cassert>
//[ifdef_function
// Use #ifdef to completely disable contract code compilation.
#include <boost/contract/core/config.hpp>
#ifndef BOOST_CONTRACT_NO_ALL
#include <boost/contract.hpp>
#endif
int inc(int& x) {
int result;
#ifndef BOOST_CONTRACT_NO_OLDS
boost::contract::old_ptr<int> old_x = BOOST_CONTRACT_OLDOF(x);
#endif
#ifndef BOOST_CONTRACT_NO_FUNCTIONS
boost::contract::check c = boost::contract::function()
#ifndef BOOST_CONTRACT_NO_PRECONDITIONS
.precondition([&] {
BOOST_CONTRACT_ASSERT(x < std::numeric_limits<int>::max());
})
#endif
#ifndef BOOST_CONTRACT_NO_POSTCONDITIONS
.postcondition([&] {
BOOST_CONTRACT_ASSERT(x == *old_x + 1);
BOOST_CONTRACT_ASSERT(result == *old_x);
})
#endif
;
#endif
return result = x++;
}
//]
template<typename T>
class pushable {
#ifndef BOOST_CONTRACT_NO_ALL
friend class boost::contract::access;
#endif
#ifndef BOOST_CONTRACT_NO_INVARIANTS
void invariant() const {
BOOST_CONTRACT_ASSERT(capacity() <= max_size());
}
#endif
public:
virtual void push_back(
T const& x
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
, boost::contract::virtual_* v = 0
#endif
) = 0;
protected:
virtual unsigned capacity() const = 0;
virtual unsigned max_size() const = 0;
};
template<typename T>
void pushable<T>::push_back(
T const& x
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
, boost::contract::virtual_* v
#endif
) {
#ifndef BOOST_CONTRACT_NO_OLDS
boost::contract::old_ptr<unsigned> old_capacity =
BOOST_CONTRACT_OLDOF(v, capacity());
#endif
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
boost::contract::check c = boost::contract::public_function(v, this)
#ifndef BOOST_CONTRACT_NO_PRECONDITIONS
.precondition([&] {
BOOST_CONTRACT_ASSERT(capacity() < max_size());
})
#endif
#ifndef BOOST_CONTRACT_NO_POSTCONDITIONS
.postcondition([&] {
BOOST_CONTRACT_ASSERT(capacity() >= *old_capacity);
})
#endif
;
#endif
assert(false); // Shall never execute this body.
}
//[ifdef_class
class integers
#define BASES public pushable<int>
:
#ifndef BOOST_CONTRACT_NO_PRECONDITIONS
private boost::contract::constructor_precondition<integers>, BASES
#else
BASES
#endif
{
#ifndef BOOST_CONTRACT_NO_ALL
friend class boost::contract::access;
#endif
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
typedef BOOST_CONTRACT_BASE_TYPES(BASES) base_types;
#endif
#undef BASES
#ifndef BOOST_CONTRACT_NO_INVARIANTS
void invariant() const {
BOOST_CONTRACT_ASSERT(size() <= capacity());
}
#endif
public:
integers(int from, int to) :
#ifndef BOOST_CONTRACT_NO_PRECONDITIONS
boost::contract::constructor_precondition<integers>([&] {
BOOST_CONTRACT_ASSERT(from <= to);
}),
#endif
vect_(to - from + 1)
{
#ifndef BOOST_CONTRACT_NO_CONSTRUCTORS
boost::contract::check c = boost::contract::constructor(this)
#ifndef BOOST_CONTRACT_NO_POSTCONDITIONS
.postcondition([&] {
BOOST_CONTRACT_ASSERT(int(size()) == (to - from + 1));
})
#endif
;
#endif
for(int x = from; x <= to; ++x) vect_.at(x - from) = x;
}
virtual ~integers() {
#ifndef BOOST_CONTRACT_NO_DESTRUCTORS
// Check invariants.
boost::contract::check c = boost::contract::destructor(this);
#endif
}
virtual void push_back(
int const& x
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
, boost::contract::virtual_* v = 0
#endif
) /* override */ {
#ifndef BOOST_CONTRACT_NO_OLDS
boost::contract::old_ptr<unsigned> old_size;
#endif
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
boost::contract::check c = boost::contract::public_function<
override_push_back>(v, &integers::push_back, this, x)
#ifndef BOOST_CONTRACT_NO_PRECONDITIONS
.precondition([&] {
BOOST_CONTRACT_ASSERT(size() < max_size());
})
#endif
#ifndef BOOST_CONTRACT_NO_OLDS
.old([&] {
old_size = BOOST_CONTRACT_OLDOF(v, size());
})
#endif
#ifndef BOOST_CONTRACT_NO_POSTCONDITIONS
.postcondition([&] {
BOOST_CONTRACT_ASSERT(size() == *old_size + 1);
})
#endif
#ifndef BOOST_CONTRACT_NO_EXCEPTS
.except([&] {
BOOST_CONTRACT_ASSERT(size() == *old_size);
})
#endif
;
#endif
vect_.push_back(x);
}
private:
#ifndef BOOST_CONTRACT_NO_PUBLIC_FUNCTIONS
BOOST_CONTRACT_OVERRIDE(push_back)
#endif
/* ... */
//]
public: // Could program contracts for these too...
unsigned size() const { return vect_.size(); }
unsigned max_size() const { return vect_.max_size(); }
unsigned capacity() const { return vect_.capacity(); }
private:
std::vector<int> vect_;
};
int main() {
integers i(1, 10);
int x = 123;
i.push_back(inc(x));
assert(x == 124);
assert(i.size() == 11);
return 0;
}
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