| QxOrm 1.4.4 C++ Object Relational Mapping library

- Main Page
- Modules
- Namespaces
- Classes
- Files
- Directories

- File List
- File Members

QxAny.h
Go to the documentation of this file.

    00001 /****************************************************************************
    00002 **
    00003 ** http://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 :
    00028 ** contact@qxorm.com
    00029 **
    00030 ****************************************************************************/
    00031
    00032 #ifndef _QX_ANY_H_
    00033 #define _QX_ANY_H_
    00034
    00035 #ifdef _MSC_VER
    00036 #pragma once
    00037 #endif
    00038
    00046 #ifndef _QX_NO_RTTI
    00047 #include <typeinfo>
    00048 #define QX_TYPE_ID(T) typeid(T)
    00049 #else // _QX_NO_RTTI
    00050 #include <QxTraits/get_class_name.h>
    00051 #include <QxTraits/get_class_name_primitive.h>
    00052 #define QX_TYPE_ID(T) std::string(qx::trait::get_class_name< T >::get())
    00053 #endif // _QX_NO_RTTI
    00054
    00055 #ifndef Q_OS_WIN
    00056 #if (__GNUC__ >= 4)
    00057 #define QX_ANY_FORCE_HIDDEN_VISIBILITY __attribute__ ((visibility("hidden"))) // To avoid a GCC warning : 'qx::any::holder<T>' declared with greater visibility than the type of its field 'qx::any::holder<T>::held' [-Wattributes]
    00058 #endif // (__GNUC__ >= 4)
    00059 #endif // Q_OS_WIN
    00060
    00061 #ifndef QX_ANY_FORCE_HIDDEN_VISIBILITY
    00062 #define QX_ANY_FORCE_HIDDEN_VISIBILITY /* Nothing */
    00063 #endif // QX_ANY_FORCE_HIDDEN_VISIBILITY
    00064
    00065 namespace qx {
    00066
    00067 class any;
    00068 template <typename ValueType> ValueType * any_cast(any *);
    00069 template <typename ValueType> ValueType * unsafe_any_cast(any *);
    00070
    00071 class any
    00072 {
    00073
    00074    template <typename ValueType> friend ValueType * qx::any_cast(any *);
    00075    template <typename ValueType> friend ValueType * qx::unsafe_any_cast(any *);
    00076
    00077 public:
    00078
    00079 #ifndef _QX_NO_RTTI
    00080    typedef const std::type_info & type_check;
    00081 #else // _QX_NO_RTTI
    00082    typedef std::string type_check;
    00083 #endif // _QX_NO_RTTI
    00084
    00085    any() : content(NULL) { ; }
    00086    any(const any & other) : content(other.content ? other.content->clone() : NULL) { ; }
    00087    ~any() { if (content) { delete content; } }
    00088
    00089    template <typename ValueType>
    00090    any(const ValueType & value) : content(new holder<typename std::remove_cv<typename std::decay<const ValueType>::type>::type>(value)) { ; }
    00091
    00092    any & swap(any & other) { std::swap(content, other.content); return (* this); }
    00093
    00094    template <typename ValueType>
    00095    any & operator=(const ValueType & other) { any(other).swap(* this); return (* this); }
    00096
    00097    any & operator=(any other) { any(other).swap(* this); return (* this); }
    00098    bool empty() const { return (! content); }
    00099    void clear() { any().swap(* this); }
    00100    type_check type() const { return (content ? content->type() : QX_TYPE_ID(void)); }
    00101
    00102 private:
    00103
    00104    struct placeholder
    00105    {
    00106       virtual ~placeholder() { ; }
    00107       virtual type_check type() const = 0;
    00108       virtual placeholder * clone() const = 0;
    00109    };
    00110
    00111    template <typename ValueType>
    00112    struct QX_ANY_FORCE_HIDDEN_VISIBILITY holder : public placeholder
    00113    {
    00114       holder(const ValueType & value) : held(value) { ; }
    00115       virtual type_check type() const { return QX_TYPE_ID(ValueType); }
    00116       virtual placeholder * clone() const { return new holder(held); }
    00117       ValueType held;
    00118
    00119       private:
    00120       holder & operator=(const holder &);
    00121    };
    00122
    00123    placeholder * content;
    00124
    00125 };
    00126
    00127 inline void swap(any & lhs, any & other) { lhs.swap(other); }
    00128
    00129 struct bad_any_cast : public std::exception
    00130 { virtual const char * what() const throw() { return "qx::bad_any_cast : failed conversion using qx::any_cast"; } };
    00131
    00132 template <typename ValueType>
    00133 ValueType * any_cast(any * operand)
    00134 { return ((operand && (operand->type() == QX_TYPE_ID(ValueType))) ? (& static_cast<any::holder<typename std::remove_cv<ValueType>::type> *>(operand->content)->held) : NULL); }
    00135
    00136 template <typename ValueType>
    00137 const ValueType * any_cast(const any * operand)
    00138 { return any_cast<ValueType>(const_cast<any *>(operand)); }
    00139
    00140 template <typename ValueType>
    00141 ValueType any_cast(any & operand)
    00142 {
    00143    typedef typename std::remove_reference<ValueType>::type nonref;
    00144    nonref * result = any_cast<nonref>(& operand);
    00145    if (! result) { throw qx::bad_any_cast(); }
    00146    return static_cast<ValueType>(* result);
    00147 }
    00148
    00149 template <typename ValueType>
    00150 ValueType any_cast(const any & operand)
    00151 {
    00152    typedef typename std::remove_reference<ValueType>::type nonref;
    00153    return any_cast<const nonref &>(const_cast<any &>(operand));
    00154 }
    00155
    00156 template <typename ValueType>
    00157 ValueType * unsafe_any_cast(any * operand)
    00158 { return (& static_cast<any::holder<ValueType> *>(operand->content)->held); }
    00159
    00160 template <typename ValueType>
    00161 const ValueType * unsafe_any_cast(const any * operand)
    00162 { return unsafe_any_cast<ValueType>(const_cast<any *>(operand)); }
    00163
    00164 } // namespace qx
    00165
    00166 #endif // _QX_ANY_H_