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/* Unit testing for outcomes
(C) 2017-2020 Niall Douglas <http://www.nedproductions.biz/> (7 commits)
Boost Software License - Version 1.0 - August 17th, 2003
Permission is hereby granted, free of charge, to any person or organization
obtaining a copy of the software and accompanying documentation covered by
this license (the "Software") to use, reproduce, display, distribute,
execute, and transmit the Software, and to prepare derivative works of the
Software, and to permit third-parties to whom the Software is furnished to
do so, all subject to the following:
The copyright notices in the Software and this entire statement, including
the above license grant, this restriction and the following disclaimer,
must be included in all copies of the Software, in whole or in part, and
all derivative works of the Software, unless such copies or derivative
works are solely in the form of machine-executable object code generated by
a source language processor.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/
#include <boost/outcome/experimental/status_result.hpp>
#include <climits> // for INT_MAX
#include <cstdio>
// status_code<erased<intptr_t>>
using error = BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::error;
// Outcome's result must be told when it is dealing with an erased status code
template <class T, class E> using result = BOOST_OUTCOME_V2_NAMESPACE::experimental::status_result<T, E, BOOST_OUTCOME_V2_NAMESPACE::policy::all_narrow>;
enum class arithmetic_errc
{
success,
divide_by_zero,
integer_divide_overflows,
not_integer_division
};
class _arithmetic_errc_domain;
using arithmetic_errc_error = BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<_arithmetic_errc_domain>;
class _arithmetic_errc_domain : public BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code_domain
{
using _base = BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code_domain;
public:
using value_type = arithmetic_errc;
constexpr explicit _arithmetic_errc_domain(typename _base::unique_id_type id = 0x290f170194f0c6c7) noexcept : _base(id) {}
static inline constexpr const _arithmetic_errc_domain &get();
virtual _base::string_ref name() const noexcept override final // NOLINT
{
static string_ref v("arithmetic error domain");
return v; // NOLINT
}
protected:
virtual bool _do_failure(const BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<void> &code) const noexcept override final // NOLINT
{
assert(code.domain() == *this); // NOLINT
const auto &c1 = static_cast<const arithmetic_errc_error &>(code); // NOLINT
return c1.value() != arithmetic_errc::success;
}
virtual bool _do_equivalent(const BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<void> &, const BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<void> &) const noexcept override final { return false; } // NOLINT
virtual BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::generic_code _generic_code(const BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<void> &) const noexcept override final { return {}; } // NOLINT
virtual _base::string_ref _do_message(const BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<void> &code) const noexcept override final // NOLINT
{
assert(code.domain() == *this); // NOLINT
const auto &c1 = static_cast<const arithmetic_errc_error &>(code); // NOLINT
switch(c1.value())
{
case arithmetic_errc::success:
return _base::string_ref("success");
case arithmetic_errc::divide_by_zero:
return _base::string_ref("divide by zero");
case arithmetic_errc::integer_divide_overflows:
return _base::string_ref("integer divide overflows");
case arithmetic_errc::not_integer_division:
return _base::string_ref("not integer division");
}
return _base::string_ref("unknown");
}
BOOST_OUTCOME_SYSTEM_ERROR2_NORETURN virtual void _do_throw_exception(const BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::status_code<void> &) const override final { abort(); } // NOLINT
};
constexpr _arithmetic_errc_domain arithmetic_errc_domain;
inline constexpr const _arithmetic_errc_domain &_arithmetic_errc_domain::get()
{
return arithmetic_errc_domain;
}
// Tell status code about the available implicit conversion
inline arithmetic_errc_error make_status_code(arithmetic_errc e)
{
return arithmetic_errc_error(BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::in_place, e);
}
BOOST_OUTCOME_V2_NAMESPACE_BEGIN
namespace trait
{
// Tell Outcome that arithmetic_errc is convertible into std::error
template <> struct is_error_type_enum<error, arithmetic_errc>
{
static constexpr bool value = true;
};
}
BOOST_OUTCOME_V2_NAMESPACE_END
// And tell Outcome how to perform the implicit conversion
inline error make_error_code(arithmetic_errc e)
{
return arithmetic_errc_error(BOOST_OUTCOME_SYSTEM_ERROR2_NAMESPACE::in_place, e);
}
result<int, error> safe_divide(int i, int j)
{
if(j == 0)
{
return arithmetic_errc::divide_by_zero;
}
if(i == INT_MIN && j == -1)
{
return arithmetic_errc::integer_divide_overflows;
}
if(i % j != 0)
{
return arithmetic_errc::not_integer_division;
}
return i / j;
}
int caller2(int i, int j)
{
auto r = safe_divide(i, j);
if(r)
{
return r.value();
}
if(r.error() == arithmetic_errc::divide_by_zero)
{
return 0;
}
if(r.error() == arithmetic_errc::not_integer_division)
{
return i / j; // ignore
}
if(r.error() == arithmetic_errc::integer_divide_overflows)
{
return INT_MIN;
}
return 0;
}
int main()
{
printf("%d\n", caller2(5, 6)); // NOLINT
return 0;
}
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