Files
sqlpp11/include/sqlpp11/assignment_list.h
2013-09-30 07:46:50 +02:00

103 lines
3.9 KiB
C++

/*
* Copyright (c) 2013, Roland Bock
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice, this
* list of conditions and the following disclaimer in the documentation and/or
* other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef SQLPP_ASSIGNMENT_LIST_H
#define SQLPP_ASSIGNMENT_LIST_H
#include <vector>
#include <sqlpp11/type_traits.h>
#include <sqlpp11/detail/set.h>
#include <sqlpp11/detail/serialize_tuple.h>
#include <sqlpp11/detail/serializable.h>
namespace sqlpp
{
namespace detail
{
template<typename Db>
struct dynamic_assignment_list
{
using type = std::vector<detail::serializable_t<Db>>;
};
template<>
struct dynamic_assignment_list<void>
{
using type = std::vector<noop>;
};
};
template<typename Database, template<typename> class ProhibitPredicate, typename... Assignments>
struct assignment_list_t
{
using _is_assignment_list = std::true_type;
using _is_dynamic = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
// check for at least one order expression
static_assert(_is_dynamic::value or sizeof...(Assignments), "at least one assignment expression required in set()");
// check for duplicate assignments
static_assert(not detail::has_duplicates<Assignments...>::value, "at least one duplicate argument detected in set()");
// check for invalid assignments
using _assignment_set = typename detail::make_set_if<is_assignment_t, Assignments...>::type;
static_assert(_assignment_set::size::value == sizeof...(Assignments), "at least one argument is not an assignment in set()");
// check for prohibited assignments
using _prohibited_assignment_set = typename detail::make_set_if<ProhibitPredicate, typename Assignments::column_type...>::type;
static_assert(_prohibited_assignment_set::size::value == 0, "at least one assignment is prohibited by its column definition in set()");
template<typename Assignment>
void add(Assignment&& assignment)
{
static_assert(is_assignment_t<typename std::decay<Assignment>::type>::value, "set() arguments require to be assigments");
static_assert(not ProhibitPredicate<typename std::decay<Assignment>::type::column_type>::value, "set() argument must not be updated");
_dynamic_assignments.push_back(std::forward<Assignment>(assignment));
}
template<typename Db>
void serialize(std::ostream& os, Db& db) const
{
os << " SET ";
detail::serialize_tuple(os, db, _assignments, ',');
bool first = sizeof...(Assignments) == 0;
for (const auto& assignment : _dynamic_assignments)
{
if (not first)
os << ',';
assignment.serialize(os, db);
first = false;
}
}
std::tuple<Assignments...> _assignments;
typename detail::dynamic_assignment_list<Database>::type _dynamic_assignments;
};
}
#endif