exceptions.hpp

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/* Copyright 2009-2017 Francesco Biscani (bluescarni@gmail.com)

This file is part of the Piranha library.

The Piranha library is free software; you can redistribute it and/or modify
it under the terms of either:

  * the GNU Lesser General Public License as published by the Free
    Software Foundation; either version 3 of the License, or (at your
    option) any later version.

or

  * the GNU General Public License as published by the Free Software
    Foundation; either version 3 of the License, or (at your option) any
    later version.

or both in parallel, as here.

The Piranha library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received copies of the GNU General Public License and the
GNU Lesser General Public License along with the Piranha library.  If not,
see https://www.gnu.org/licenses/. */

#ifndef PIRANHA_EXCEPTIONS_HPP
#define PIRANHA_EXCEPTIONS_HPP

#include <stdexcept>
#include <string>
#include <type_traits>
#include <utility>

#include <piranha/type_traits.hpp>

namespace piranha
{
inline namespace impl
{

template <typename Exception>
struct ex_thrower {
    // Determine the type of the __LINE__ macro.
    using line_type = uncvref_t<decltype(__LINE__)>;
    explicit ex_thrower(const char *file, line_type line, const char *func) : m_file(file), m_line(line), m_func(func)
    {
    }
    template <typename... Args, typename = enable_if_t<std::is_constructible<Exception, Args &&...>::value>>
    [[noreturn]] void operator()(Args &&... args) const
    {
        throw Exception(std::forward<Args>(args)...);
    }
    template <typename Str>
    using str_add_t = decltype(std::declval<std::string &>() += std::declval<Str>());
    template <typename Str, typename... Args,
              typename = enable_if_t<conjunction<std::is_constructible<Exception, std::string, Args &&...>,
                                                 is_detected<str_add_t, Str &&>>::value>>
    [[noreturn]] void operator()(Str &&desc, Args &&... args) const
    {
        std::string msg("\nfunction: ");
        msg += m_func;
        msg += "\nwhere: ";
        msg += m_file;
        msg += ", ";
        msg += std::to_string(m_line);
        msg += "\nwhat: ";
        msg += std::forward<Str>(desc);
        msg += "\n";
        throw Exception(msg, std::forward<Args>(args)...);
    }
    const char *m_file;
    const line_type m_line;
    const char *m_func;
};
}
}


// NOTE: we need the struct here because we need to split off the __VA_ARGS__ into a separate function call, otherwise
// there could be situations in which the throwing function would be called with a set of arguments (a,b,c,), which
// would be invalid syntax.
#define piranha_throw(exception_type, ...)                                                                             \
    piranha::ex_thrower<exception_type>(__FILE__, __LINE__, __func__)(__VA_ARGS__)

namespace piranha
{


struct not_implemented_error final : std::runtime_error {
    using std::runtime_error::runtime_error;
};


struct zero_division_error final : std::domain_error {
    using std::domain_error::domain_error;
};
}

#endif