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89 lines
2.9 KiB
C++
89 lines
2.9 KiB
C++
/*
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* Copyright (c) 2013-2014, Roland Bock
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification,
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* are permitted provided that the following conditions are met:
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*
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* Redistributions of source code must retain the above copyright notice, this
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* list of conditions and the following disclaimer.
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*
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* Redistributions in binary form must reproduce the above copyright notice, this
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* list of conditions and the following disclaimer in the documentation and/or
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* other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
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* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#ifndef SQLPP_IS_NULL_H
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#define SQLPP_IS_NULL_H
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#include <sqlpp11/boolean.h>
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#include <sqlpp11/type_traits.h>
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#include <sqlpp11/detail/type_set.h>
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namespace sqlpp
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{
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template<bool NotInverted, typename Operand>
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struct is_null_t: public boolean::template expression_operators<is_null_t<NotInverted, Operand>>,
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public alias_operators<is_null_t<NotInverted, Operand>>
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{
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using _traits = make_traits<boolean, ::sqlpp::tag::is_expression, ::sqlpp::tag::is_named_expression>;
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using _recursive_traits = make_recursive_traits<Operand>;
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static constexpr bool _inverted = not NotInverted;
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struct _value_type: public boolean
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{
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using _is_named_expression = std::true_type;
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};
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struct _name_t
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{
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static constexpr const char* _get_name() { return _inverted ? "IS NOT NULL" : "IS NULL"; }
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template<typename T>
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struct _member_t
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{
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T in;
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};
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};
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is_null_t(Operand operand):
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_operand(operand)
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{}
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is_null_t(const is_null_t&) = default;
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is_null_t(is_null_t&&) = default;
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is_null_t& operator=(const is_null_t&) = default;
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is_null_t& operator=(is_null_t&&) = default;
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~is_null_t() = default;
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Operand _operand;
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};
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template<typename Context, bool NotInverted, typename Operand>
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struct serializer_t<Context, ::sqlpp::is_null_t<NotInverted, Operand>>
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{
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using T = ::sqlpp::is_null_t<NotInverted, Operand>;
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static Context& _(const T& t, Context& context)
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{
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serialize(t._operand, context);
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context << (t._inverted ? " IS NOT NULL" : " IS NULL");
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return context;
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}
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};
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}
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#endif
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