QxOrm  1.4.5
C++ Object Relational Mapping library
QxStdOptional.h
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00001 /****************************************************************************
00002 **
00003 ** https://www.qxorm.com/
00004 ** Copyright (C) 2013 Lionel Marty (contact@qxorm.com)
00005 **
00006 ** This file is part of the QxOrm library
00007 **
00008 ** This software is provided 'as-is', without any express or implied
00009 ** warranty. In no event will the authors be held liable for any
00010 ** damages arising from the use of this software
00011 **
00012 ** Commercial Usage
00013 ** Licensees holding valid commercial QxOrm licenses may use this file in
00014 ** accordance with the commercial license agreement provided with the
00015 ** Software or, alternatively, in accordance with the terms contained in
00016 ** a written agreement between you and Lionel Marty
00017 **
00018 ** GNU General Public License Usage
00019 ** Alternatively, this file may be used under the terms of the GNU
00020 ** General Public License version 3.0 as published by the Free Software
00021 ** Foundation and appearing in the file 'license.gpl3.txt' included in the
00022 ** packaging of this file. Please review the following information to
00023 ** ensure the GNU General Public License version 3.0 requirements will be
00024 ** met : http://www.gnu.org/copyleft/gpl.html
00025 **
00026 ** If you are unsure which license is appropriate for your use, or
00027 ** if you have questions regarding the use of this file, please contact :
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00031 
00032 #ifndef _QX_STD_OPTIONAL_H_
00033 #define _QX_STD_OPTIONAL_H_
00034 
00035 #ifdef _MSC_VER
00036 #pragma once
00037 #endif
00038 
00046 #include <optional>
00047 
00048 #include <QtCore/qdatastream.h>
00049 
00050 #include <QxOrm.h>
00051 
00052 #include <QxTraits/construct_null_qvariant.h>
00053 
00054 template <typename T>
00055 QDataStream & operator<< (QDataStream & stream, const std::optional<T> & t)
00056 {
00057    qint8 iHasData = (t ? 1 : 0);
00058    stream << iHasData;
00059    if (t) { stream << (* t); }
00060    return stream;
00061 }
00062 
00063 template <typename T>
00064 QDataStream & operator>> (QDataStream & stream, std::optional<T> & t)
00065 {
00066    qint8 iHasData = 0;
00067    stream >> iHasData;
00068    if (iHasData) { t = T(); stream >> (* t); }
00069    else { t = std::optional<T>(); }
00070    return stream;
00071 }
00072 
00073 QX_REGISTER_CLASS_NAME_TEMPLATE_1(std::optional)
00074 
00075 namespace qx {
00076 namespace trait {
00077 
00078 template <typename T>
00079 struct get_sql_type< std::optional<T> >
00080 { static inline const char * get() { return qx::trait::get_sql_type<T>::get(); } };
00081 
00082 } // namespace trait
00083 } // namespace qx
00084 
00085 namespace qx {
00086 namespace cvt {
00087 namespace detail {
00088 
00089 #ifndef _QX_NO_JSON
00090 
00091 template <typename T> struct QxConvert_ToJson< std::optional<T> > {
00092 static inline QJsonValue toJson(const std::optional<T> & t, const QString & format)
00093 { if (t) { return qx::cvt::to_json((* t), format); }; return QJsonValue(); } };
00094 
00095 template <typename T> struct QxConvert_FromJson< std::optional<T> > {
00096 static inline qx_bool fromJson(const QJsonValue & j, std::optional<T> & t, const QString & format)
00097 {
00098    if (j.isNull()) { t = std::optional<T>(); return qx_bool(true); }
00099    else if (! t) { t = T(); }
00100    return qx::cvt::from_json(j, (* t), format);
00101 } };
00102 
00103 #endif // _QX_NO_JSON
00104 
00105 template <typename T> struct QxConvert_ToString< std::optional<T> > {
00106 static inline QString toString(const std::optional<T> & t, const QString & format, int index, qx::cvt::context::ctx_type ctx)
00107 { if (t) { return qx::cvt::to_string((* t), format, index, ctx); }; return QString(); } };
00108 
00109 template <typename T> struct QxConvert_FromString< std::optional<T> > {
00110 static inline qx_bool fromString(const QString & s, std::optional<T> & t, const QString & format, int index, qx::cvt::context::ctx_type ctx)
00111 { if (! t) { t = T(); }; return qx::cvt::from_string(s, (* t), format, index, ctx); } };
00112 
00113 template <typename T> struct QxConvert_ToVariant< std::optional<T> > {
00114 static inline QVariant toVariant(const std::optional<T> & t, const QString & format, int index, qx::cvt::context::ctx_type ctx)
00115 { if (t) { return qx::cvt::to_variant((* t), format, index, ctx); }; return qx::trait::construct_null_qvariant<T>::get(); } };
00116 
00117 template <typename T> struct QxConvert_FromVariant< std::optional<T> > {
00118 static inline qx_bool fromVariant(const QVariant & v, std::optional<T> & t, const QString & format, int index, qx::cvt::context::ctx_type ctx)
00119 {
00120    if (v.isNull()) { t = std::optional<T>(); return qx_bool(true); }
00121    else if (! t) { t = T(); }
00122    return qx::cvt::from_variant(v, (* t), format, index, ctx);
00123 } };
00124 
00125 } // namespace detail
00126 } // namespace cvt
00127 } // namespace qx
00128 
00129 #endif // _QX_STD_OPTIONAL_H_