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mirror of https://github.com/rbock/sqlpp11.git synced 2024-11-16 04:47:18 +08:00
sqlpp11/include/sqlpp11/floating_point.h
rbock 4ac4b1820b Removed stray sqlpp namespace qualifiers
The usage was very inconsistent. Also, I just saw that the current VC++
cannot deal with qualifiers in combination with template aliases
2014-08-27 20:43:09 +02:00

293 lines
7.8 KiB
C++

/*
* Copyright (c) 2013-2014, 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_FLOATING_POINT_H
#define SQLPP_FLOATING_POINT_H
#include <cstdlib>
#include <sqlpp11/basic_expression_operators.h>
#include <sqlpp11/type_traits.h>
#include <sqlpp11/exception.h>
#include <sqlpp11/result_field.h>
namespace sqlpp
{
// floating_point value type
struct floating_point
{
using _traits = make_traits<floating_point, tag::is_value_type>;
using _tag = tag::is_floating_point;
using _cpp_value_type = double;
template<typename T>
using _is_valid_operand = is_numeric_t<T>;
};
// floating_point parameter type
template<>
struct parameter_value_t<floating_point>
{
using _value_type = floating_point;
using _cpp_value_type = typename _value_type::_cpp_value_type;
parameter_value_t():
_value(0),
_is_null(true)
{}
parameter_value_t(const _cpp_value_type& value):
_value(value),
_is_null(false)
{}
parameter_value_t& operator=(const _cpp_value_type& value)
{
_value = value;
_is_null = false;
return *this;
}
parameter_value_t& operator=(const tvin_t<wrap_operand_t<_cpp_value_type>>& t)
{
if (t._is_trivial())
{
_value = 0;
_is_null = true;
}
else
{
_value = t._value._t;
_is_null = false;
}
return *this;
}
parameter_value_t& operator=(const std::nullptr_t&)
{
_value = 0;
_is_null = true;
return *this;
}
bool is_null() const
{
return _is_null;
}
const _cpp_value_type& value() const
{
return _value;
}
operator _cpp_value_type() const { return _value; }
template<typename Target>
void _bind(Target& target, size_t index) const
{
target._bind_floating_point_parameter(index, &_value, _is_null);
}
private:
_cpp_value_type _value;
bool _is_null;
};
// floating_point expression operators
template<typename Expr>
struct expression_operators<Expr, floating_point>:
public basic_expression_operators<Expr, floating_point>
{
template<typename T>
using _is_valid_operand = is_valid_operand<floating_point, T>;
template<typename T>
plus_t<Expr, floating_point, wrap_operand_t<T>> operator +(T t) const
{
using rhs = wrap_operand_t<T>;
static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
return { *static_cast<const Expr*>(this), rhs{t} };
}
template<typename T>
minus_t<Expr, floating_point, wrap_operand_t<T>> operator -(T t) const
{
using rhs = wrap_operand_t<T>;
static_assert(_is_valid_operand<rhs>::value, "invalid rhs operand");
return { *static_cast<const Expr*>(this), rhs{t} };
}
template<typename T>
multiplies_t<Expr, floating_point, wrap_operand_t<T>> operator *(T t) const
{
using rhs = wrap_operand_t<T>;
return { *static_cast<const Expr*>(this), rhs{t} };
}
template<typename T>
divides_t<Expr, wrap_operand_t<T>> operator /(T t) const
{
using rhs = wrap_operand_t<T>;
return { *static_cast<const Expr*>(this), rhs{t} };
}
unary_plus_t<floating_point, Expr> operator +() const
{
return { *static_cast<const Expr*>(this) };
}
unary_minus_t<floating_point, Expr> operator -() const
{
return { *static_cast<const Expr*>(this) };
}
};
// floating_point column operators
template<typename Column>
struct column_operators<Column, floating_point>
{
template<typename T>
using _is_valid_operand = is_valid_operand<floating_point, T>;
template<typename T>
auto operator +=(T t) const -> assignment_t<Column, plus_t<Column, floating_point, wrap_operand_t<T>>>
{
using rhs = wrap_operand_t<T>;
static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
return { *static_cast<const Column*>(this), { *static_cast<const Column*>(this), rhs{t} } };
}
template<typename T>
auto operator -=(T t) const -> assignment_t<Column, minus_t<Column, floating_point, wrap_operand_t<T>>>
{
using rhs = wrap_operand_t<T>;
static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
return { *static_cast<const Column*>(this), { *static_cast<const Column*>(this), rhs{t} } };
}
template<typename T>
auto operator /=(T t) const -> assignment_t<Column, divides_t<Column, wrap_operand_t<T>>>
{
using rhs = wrap_operand_t<T>;
static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
return { *static_cast<const Column*>(this), { *static_cast<const Column*>(this), rhs{t} } };
}
template<typename T>
auto operator *=(T t) const -> assignment_t<Column, multiplies_t<Column, floating_point, wrap_operand_t<T>>>
{
using rhs = wrap_operand_t<T>;
static_assert(_is_valid_operand<rhs>::value, "invalid rhs assignment operand");
return { *static_cast<const Column*>(this), { *static_cast<const Column*>(this), rhs{t} } };
}
};
// floating_point result field
template<typename Db, typename FieldSpec>
struct result_field_t<floating_point, Db, FieldSpec>: public result_field_methods_t<result_field_t<floating_point, Db, FieldSpec>>
{
static_assert(std::is_same<value_type_of<FieldSpec>, floating_point>::value, "field type mismatch");
using _cpp_value_type = typename floating_point::_cpp_value_type;
result_field_t():
_is_valid(false),
_is_null(true),
_value(0)
{}
void _validate()
{
_is_valid = true;
}
void _invalidate()
{
_is_valid = false;
_is_null = true;
_value = 0;
}
bool is_null() const
{
if (not _is_valid)
throw exception("accessing is_null in non-existing row");
return _is_null;
}
bool _is_trivial() const
{
if (not _is_valid)
throw exception("accessing is_null in non-existing row");
return value() == 0;
}
_cpp_value_type value() const
{
if (not _is_valid)
throw exception("accessing value in non-existing row");
if (_is_null)
{
if (enforce_null_result_treatment_t<Db>::value and not null_is_trivial_value_t<FieldSpec>::value)
{
throw exception("accessing value of NULL field");
}
else
{
return 0;
}
}
return _value;
}
template<typename Target>
void _bind(Target& target, size_t i)
{
target._bind_floating_point_result(i, &_value, &_is_null);
}
private:
bool _is_valid;
bool _is_null;
_cpp_value_type _value;
};
template<typename Db, typename FieldSpec>
inline std::ostream& operator<<(std::ostream& os, const result_field_t<floating_point, Db, FieldSpec>& e)
{
return serialize(e, os);
}
}
#endif