Files
sqlpp11/include/sqlpp11/basic_expression_operators.h
rbock 173d6adbc9 Moved data types into separate folder, split boolean
Each file within data_types/boolean/ is relatively short and easy to
grok.
2015-10-29 22:21:46 +01:00

225 lines
8.1 KiB
C++

/*
* Copyright (c) 2013-2015, 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_DETAIL_BASIC_EXPRESSION_OPERATORS_H
#define SQLPP_DETAIL_BASIC_EXPRESSION_OPERATORS_H
#include <sqlpp11/value_type_fwd.h>
#include <sqlpp11/bad_statement.h>
#include <sqlpp11/portable_static_assert.h>
#include <sqlpp11/consistent.h>
#include <sqlpp11/alias.h>
#include <sqlpp11/sort_order.h>
#include <sqlpp11/expression_fwd.h>
#include <sqlpp11/in_fwd.h>
#include <sqlpp11/is_null_fwd.h>
#include <sqlpp11/wrap_operand.h>
#include <sqlpp11/logic.h>
namespace sqlpp
{
SQLPP_PORTABLE_STATIC_ASSERT(assert_valid_rhs_comparison_operand_t, "invalid rhs operand in comparison");
template <typename LhsValueType, typename RhsType>
using check_rhs_comparison_operand_t =
static_check_t<(is_expression_t<sqlpp::wrap_operand_t<RhsType>>::value // expressions are OK
or
is_multi_expression_t<sqlpp::wrap_operand_t<RhsType>>::value) // multi-expressions like ANY are
// OK for comparisons, too
and
LhsValueType::template _is_valid_operand<
sqlpp::wrap_operand_t<RhsType>>::value, // the correct value type is required, of course
assert_valid_rhs_comparison_operand_t>;
SQLPP_PORTABLE_STATIC_ASSERT(assert_valid_in_arguments_t, "at least one operand of in() is not valid");
template <typename LhsValueType, typename... InTypes>
using check_rhs_in_arguments_t =
static_check_t<logic::all_t<check_rhs_comparison_operand_t<LhsValueType, InTypes>::value...>::value,
assert_valid_in_arguments_t>;
namespace detail
{
template <bool Enable, template <typename Lhs> class Expr, typename Lhs>
struct new_unary_expression_impl
{
using type = bad_statement;
};
template <template <typename Lhs> class Expr, typename Lhs>
struct new_unary_expression_impl<true, Expr, Lhs>
{
using type = Expr<Lhs>;
};
}
template <typename Check, template <typename Lhs> class Expr, typename Lhs>
using new_unary_expression_t = typename detail::new_unary_expression_impl<Check::value, Expr, Lhs>::type;
namespace detail
{
template <bool Enable, template <typename Lhs, typename Rhs> class Expr, typename Lhs, typename Rhs>
struct new_binary_expression_impl
{
using type = bad_statement;
};
template <template <typename Lhs, typename Rhs> class Expr, typename Lhs, typename Rhs>
struct new_binary_expression_impl<true, Expr, Lhs, Rhs>
{
using type = Expr<Lhs, Rhs>;
};
}
template <typename Check, template <typename Lhs, typename Rhs> class Expr, typename Lhs, typename Rhs>
using new_binary_expression_t = typename detail::new_binary_expression_impl<Check::value, Expr, Lhs, Rhs>::type;
namespace detail
{
template <bool Enable, template <typename Lhs, typename... Rhs> class Expr, typename Lhs, typename... Rhs>
struct new_nary_expression_impl
{
using type = bad_statement;
};
template <template <typename Lhs, typename... Rhs> class Expr, typename Lhs, typename... Rhs>
struct new_nary_expression_impl<true, Expr, Lhs, Rhs...>
{
using type = Expr<Lhs, Rhs...>;
};
}
template <typename Check, template <typename Lhs, typename... Rhs> class Expr, typename Lhs, typename... Rhs>
using new_nary_expression_t = typename detail::new_nary_expression_impl<Check::value, Expr, Lhs, Rhs...>::type;
// basic operators
template <typename Expr, typename ValueType>
struct basic_expression_operators
{
template <template <typename Lhs, typename Rhs> class NewExpr, typename T>
using _new_binary_expression_t =
new_binary_expression_t<check_rhs_comparison_operand_t<ValueType, wrap_operand_t<T>>,
NewExpr,
Expr,
wrap_operand_t<T>>;
template <template <typename Lhs, typename... Rhs> class NewExpr, typename... T>
using _new_nary_expression_t =
new_nary_expression_t<logic::all_t<check_rhs_comparison_operand_t<ValueType, wrap_operand_t<T>>::value...>,
NewExpr,
Expr,
wrap_operand_t<T>...>;
template <typename T>
_new_binary_expression_t<equal_to_t, T> operator==(T t) const
{
using rhs = wrap_operand_t<T>;
check_rhs_comparison_operand_t<ValueType, rhs>::_();
return {*static_cast<const Expr*>(this), {rhs{t}}};
}
template <typename T>
_new_binary_expression_t<not_equal_to_t, T> operator!=(T t) const
{
using rhs = wrap_operand_t<T>;
check_rhs_comparison_operand_t<ValueType, rhs>::_();
return {*static_cast<const Expr*>(this), {rhs{t}}};
}
template <typename T>
_new_binary_expression_t<less_than_t, T> operator<(T t) const
{
using rhs = wrap_operand_t<T>;
check_rhs_comparison_operand_t<ValueType, rhs>::_();
return {*static_cast<const Expr*>(this), rhs{t}};
}
template <typename T>
_new_binary_expression_t<less_equal_t, T> operator<=(T t) const
{
using rhs = wrap_operand_t<T>;
check_rhs_comparison_operand_t<ValueType, rhs>::_();
return {*static_cast<const Expr*>(this), rhs{t}};
}
template <typename T>
_new_binary_expression_t<greater_than_t, T> operator>(T t) const
{
using rhs = wrap_operand_t<T>;
check_rhs_comparison_operand_t<ValueType, rhs>::_();
return {*static_cast<const Expr*>(this), rhs{t}};
}
template <typename T>
_new_binary_expression_t<greater_equal_t, T> operator>=(T t) const
{
using rhs = wrap_operand_t<T>;
check_rhs_comparison_operand_t<ValueType, rhs>::_();
return {*static_cast<const Expr*>(this), rhs{t}};
}
is_null_t<Expr> is_null() const
{
return {*static_cast<const Expr*>(this)};
}
is_not_null_t<Expr> is_not_null() const
{
return {*static_cast<const Expr*>(this)};
}
sort_order_t<Expr, sort_type::asc> asc() const
{
return {*static_cast<const Expr*>(this)};
}
sort_order_t<Expr, sort_type::desc> desc() const
{
return {*static_cast<const Expr*>(this)};
}
// Hint: use value_list wrapper for containers...
template <typename... T>
_new_nary_expression_t<in_t, T...> in(T... t) const
{
check_rhs_in_arguments_t<ValueType, wrap_operand_t<T>...>::_();
return {*static_cast<const Expr*>(this), wrap_operand_t<T>{t}...};
}
template <typename... T>
_new_nary_expression_t<not_in_t, T...> not_in(T... t) const
{
check_rhs_in_arguments_t<ValueType, wrap_operand_t<T>...>::_();
return {*static_cast<const Expr*>(this), wrap_operand_t<T>{t}...};
}
};
}
#endif