mirror of
https://github.com/rbock/sqlpp11.git
synced 2024-11-16 12:51:13 +08:00
9c75c7b873
The code is much easier to read, the optimizer should take care of pretty much everything, AND it copiles even faster without the code being riddled with std::forward and std::decay
82 lines
3.0 KiB
C++
82 lines
3.0 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_ON_H
|
|
#define SQLPP_ON_H
|
|
|
|
#include <sqlpp11/type_traits.h>
|
|
#include <sqlpp11/detail/set.h>
|
|
#include <sqlpp11/vendor/interpret_tuple.h>
|
|
#include <sqlpp11/vendor/interpretable_list.h>
|
|
|
|
namespace sqlpp
|
|
{
|
|
template<typename Database, typename... Expr>
|
|
struct on_t
|
|
{
|
|
using _is_on = std::true_type;
|
|
using _is_dynamic = typename std::conditional<std::is_same<Database, void>::value, std::false_type, std::true_type>::type;
|
|
|
|
static_assert(_is_dynamic::value or sizeof...(Expr), "at least one expression argument required in on()");
|
|
using _valid_expressions = typename detail::make_set_if<is_expression_t, Expr...>::type;
|
|
static_assert(_valid_expressions::size::value == sizeof...(Expr), "at least one argument is not an expression in on()");
|
|
|
|
template<typename E>
|
|
void add(E expr)
|
|
{
|
|
static_assert(is_expression_t<E>::value, "invalid expression argument in add_on()");
|
|
_dynamic_expressions.emplace_back(expr);
|
|
}
|
|
|
|
std::tuple<Expr...> _expressions;
|
|
vendor::interpretable_list_t<Database> _dynamic_expressions;
|
|
};
|
|
|
|
namespace vendor
|
|
{
|
|
template<typename Context, typename Database, typename... Expr>
|
|
struct interpreter_t<Context, on_t<Database, Expr...>>
|
|
{
|
|
using T = on_t<Database, Expr...>;
|
|
|
|
static Context& _(const T& t, Context& context)
|
|
{
|
|
if (sizeof...(Expr) == 0 and t._dynamic_expressions.empty())
|
|
return context;
|
|
context << " ON ";
|
|
interpret_tuple(t._expressions, " AND ", context);
|
|
if (sizeof...(Expr) and not t._dynamic_expressions.empty())
|
|
context << " AND ";
|
|
interpret_list(t._dynamic_expressions, " AND ", context);
|
|
return context;
|
|
}
|
|
};
|
|
|
|
}
|
|
}
|
|
|
|
#endif
|