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source: code/branches/cpp11_v2/src/libraries/core/command/Functor.h @ 10985

Last change on this file since 10985 was 10985, checked in by landauf, 8 years ago

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1/*
2 *   ORXONOX - the hottest 3D action shooter ever to exist
3 *                    > www.orxonox.net <
4 *
5 *
6 *   License notice:
7 *
8 *   This program is free software; you can redistribute it and/or
9 *   modify it under the terms of the GNU General Public License
10 *   as published by the Free Software Foundation; either version 2
11 *   of the License, or (at your option) any later version.
12 *
13 *   This program is distributed in the hope that it will be useful,
14 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *   GNU General Public License for more details.
17 *
18 *   You should have received a copy of the GNU General Public License
19 *   along with this program; if not, write to the Free Software
20 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
21 *
22 *   Author:
23 *      Fabian 'x3n' Landau
24 *   Co-authors:
25 *      ...
26 *
27 */
28
29/**
30    @file
31    @ingroup Command FunctorExecutor
32    @brief Definition of orxonox::Functor and its specialized subclasses, as well as the createFunctor() functions.
33
34    @anchor FunctorExample
35
36    Functors can be used to wrap function-pointers. While function-pointers have a very
37    complicated syntax in C++, Functors are always the same and you can call the wrapped
38    function-pointer independently of its parameter with arguments of type MultiType. These
39    arguments are then automatically converted to the right type.
40
41    To create a Functor, the helper function createFunctor() is used. It returns an instance
42    of orxonox::FunctorPtr which is simply a typedef of "std::shared_ptr<Functor>". This
43    means you don't have to delete the Functor after using it, because it is managed
44    by the std::shared_ptr.
45
46    Example:
47    @code
48    int myStaticFunction(int value)                         // Definition of a static function
49    {
50        return (value * 2);                                 // Return the double of the value
51    }
52
53    FunctorPtr functor = createFunctor(&myStaticFunction);  // Create a Functor
54
55    int result = (*functor)(5);                             // Calls the functor with value = 5, result == 10
56
57    int result = (*functor)("7");                           // Calls the functor with a string which is converted to an integer, result == 14
58    @endcode
59
60    Functors can also be used if you work with member-functions. In this case createFunctor()
61    returns an instance of orxonox::FunctorMemberPtr - this allows you to define the object
62    that will be used to call the function.
63
64    Example:
65    @code
66    class MyClass                                                   // Define a class
67    {
68        public:
69            MyClass(const std::string& text)                        // Constructor
70            {
71                this->text_ = text;
72            }
73
74            bool contains(const std::string& word)                  // Function that searches for "word" in "text"
75            {
76                return (this->text_.find(word) != std::string::npos);
77            }
78
79        private:
80            std::string text_;                                      // Member variable
81    };
82
83    MyClass* object = new MyClass("Hello World");                   // Create an object of type MyClass and set its text to "Hello World"
84
85    FunctorPtr functor = createFunctor(&MyClass:contains, object);  // Create a Functor (note the object!)
86
87    bool result = (*functor)("World");                              // result == true
88    bool result = (*functor)("test");                               // result == false
89    @endcode
90
91    Instead of assigning the object directly to the functor when creating it, you can also define
92    it at any later point or when you call the functor. Note however that this works only with
93    orxonox::FunctorMember.
94
95    @code
96    MyClass* object1 = new MyClass("Hello World");                  // Create an object
97    MyClass* object2 = new MyClass("this is a test");               // Create another object
98
99    FunctorMemberPtr functor = createFunctor(&MyClass:contains);    // Create a FunctorMember (note: no object this time)
100
101    bool result = (*functor)("World");                              // result == false and an error: "Error: Can't execute FunctorMember, no object set."
102
103    bool result = (*functor)(object1, "World");                     // result == true
104    bool result = (*functor)(object1, "test");                      // result == false
105    bool result = (*functor)(object2, "test");                      // result == true
106
107    functor->setObject(object1);                                    // Assign an object to the FunctorMember
108
109    bool result = (*functor)("World");                              // result == true (no error this time, because the object was set using setObject())
110    @endcode
111*/
112
113#ifndef _Functor_H__
114#define _Functor_H__
115
116#include "core/CorePrereqs.h"
117
118#include <typeinfo>
119
120#include "util/Output.h"
121#include "util/MultiType.h"
122#include "core/object/Destroyable.h"
123#include "FunctorPtr.h"
124
125namespace orxonox
126{
127    const unsigned int MAX_FUNCTOR_ARGUMENTS = 5;   ///< The maximum number of parameters of a function that is supported by Functor
128
129    namespace detail
130    {
131        template <class T>
132        inline std::string _typeToString() { return "unknown"; }
133
134        template <> inline std::string _typeToString<void>()               { return "void"; }
135        template <> inline std::string _typeToString<int>()                { return "int"; }
136        template <> inline std::string _typeToString<unsigned int>()       { return "uint"; }
137        template <> inline std::string _typeToString<char>()               { return "char"; }
138        template <> inline std::string _typeToString<unsigned char>()      { return "uchar"; }
139        template <> inline std::string _typeToString<short>()              { return "short"; }
140        template <> inline std::string _typeToString<unsigned short>()     { return "ushort"; }
141        template <> inline std::string _typeToString<long>()               { return "long"; }
142        template <> inline std::string _typeToString<unsigned long>()      { return "ulong"; }
143        template <> inline std::string _typeToString<long long>()          { return "longlong"; }
144        template <> inline std::string _typeToString<unsigned long long>() { return "ulonglong"; }
145        template <> inline std::string _typeToString<float>()              { return "float"; }
146        template <> inline std::string _typeToString<double>()             { return "double"; }
147        template <> inline std::string _typeToString<long double>()        { return "longdouble"; }
148        template <> inline std::string _typeToString<bool>()               { return "bool"; }
149        template <> inline std::string _typeToString<std::string>()        { return "string"; }
150        template <> inline std::string _typeToString<Vector2>()            { return "Vector2"; }
151        template <> inline std::string _typeToString<Vector3>()            { return "Vector3"; }
152        template <> inline std::string _typeToString<Quaternion>()         { return "Quaternion"; }
153        template <> inline std::string _typeToString<ColourValue>()        { return "ColourValue"; }
154        template <> inline std::string _typeToString<Radian>()             { return "Radian"; }
155        template <> inline std::string _typeToString<Degree>()             { return "Degree"; }
156    }
157
158    /// Returns the name of type @a T as string.
159    template <class T>
160    inline std::string typeToString() { return detail::_typeToString<typename Loki::TypeTraits<T>::UnqualifiedReferredType>(); }
161
162    /**
163        @brief The Functor classes are used to wrap function pointers.
164
165        Function-pointers in C++ have a pretty complicated syntax and you can't store
166        and call them unless you know the exact type. A Functor can be used to wrap
167        a function-pointer and to store it independent of its type. You can also call
168        it independently of its parameters by passing the arguments as MultiType. They
169        are converted automatically to the right type.
170
171        Functor is a pure virtual base class.
172
173        @see See @ref FunctorExample "Functor.h" for some examples.
174    */
175    class _CoreExport Functor
176    {
177        public:
178            struct Type
179            {
180                /// Defines the type of a function (static or member)
181                enum Enum
182                {
183                    Static,
184                    Member
185                };
186            };
187
188        public:
189            virtual ~Functor() {}
190
191            /// Calls the function-pointer with up to five arguments. In case of a member-function, the assigned object-pointer is used to call the function. @return Returns the return-value of the function (if any; MultiType::Null otherwise)
192            virtual MultiType operator()(const MultiType& param1 = MultiType::Null, const MultiType& param2 = MultiType::Null, const MultiType& param3 = MultiType::Null, const MultiType& param4 = MultiType::Null, const MultiType& param5 = MultiType::Null) = 0;
193
194            /// Creates a new instance of Functor with the same values like this (used instead of a copy-constructor)
195            virtual FunctorPtr clone() = 0;
196
197            /// Returns the type of the function: static or member.
198            virtual Type::Enum getType() const = 0;
199            /// Returns the number of parameters of the function.
200            virtual unsigned int getParamCount() const = 0;
201            /// Returns true if the function has a return-value.
202            virtual bool hasReturnvalue() const = 0;
203
204            /// Returns the type-name of the parameter with given index (the first parameter has index 0).
205            virtual std::string getTypenameParam(unsigned int index) const = 0;
206            /// Returns the type-name of the return-value.
207            virtual std::string getTypenameReturnvalue() const = 0;
208
209            /// Converts a given argument to the type of the parameter with given index (the first parameter has index 0).
210            virtual void evaluateArgument(unsigned int index, MultiType& argument) const = 0;
211
212            /// Assigns an object-pointer to the functor which is used to execute a member-function.
213            virtual void setRawObjectPointer(void* object) = 0;
214            /// Returns the object-pointer.
215            virtual void* getRawObjectPointer() const = 0;
216
217            /// Enables or disables the safe mode which causes the functor to change the object pointer to nullptr if the object is deleted (only member functors).
218            virtual void setSafeMode(bool bSafeMode) = 0;
219
220            /// Returns the full identifier of the function-pointer which is defined as typeid(@a F), where @a F is the type of the stored function-pointer. Used to compare functors.
221            virtual const std::type_info& getFullIdentifier() const = 0;
222            /// Returns an identifier of the header of the function (doesn't include the function's class). Used to compare functors.
223            virtual const std::type_info& getHeaderIdentifier() const = 0;
224            /// Returns an identifier of the header of the function (doesn't include the function's class), but regards only the first @a params parameters. Used to compare functions if an Executor provides default-values for the other parameters.
225            virtual const std::type_info& getHeaderIdentifier(unsigned int params) const = 0;
226    };
227
228    /**
229        @brief FunctorMember is a child class of Functor and expands it with an object-pointer, that
230        is used for member-functions, as well as an overloaded execution operator.
231
232        @param O The type of the function's class (or void if it's a static function)
233
234        Note that FunctorMember is also used for static functions, but with T = void. FunctorStatic
235        is a typedef of FunctorMember<void>. The void* object-pointer is ignored in this case.
236
237        @see See @ref FunctorExample "Functor.h" for some examples.
238    */
239    template <class O>
240    class FunctorMember : public Functor, public DestructionListener
241    {
242        public:
243            /// Constructor: Stores the object-pointer.
244            FunctorMember(O* object = nullptr) : object_(object), bSafeMode_(false) {}
245            virtual ~FunctorMember() { if (this->bSafeMode_) { this->unregisterObject(this->object_); } }
246
247            /// Calls the function-pointer with up to five arguments and an object. In case of a static-function, the object can be nullptr. @return Returns the return-value of the function (if any; MultiType::Null otherwise)
248            virtual MultiType operator()(O* object, const MultiType& param1 = MultiType::Null, const MultiType& param2 = MultiType::Null, const MultiType& param3 = MultiType::Null, const MultiType& param4 = MultiType::Null, const MultiType& param5 = MultiType::Null) = 0;
249
250            // see Functor::operator()()
251            virtual MultiType operator()(const MultiType& param1 = MultiType::Null, const MultiType& param2 = MultiType::Null, const MultiType& param3 = MultiType::Null, const MultiType& param4 = MultiType::Null, const MultiType& param5 = MultiType::Null) override
252            {
253                // call the function if an object was assigned
254                if (this->object_)
255                    return (*this)(this->object_, param1, param2, param3, param4, param5);
256                else
257                {
258                    orxout(internal_error) << "Can't execute FunctorMember, no object set." << endl;
259                    return MultiType::Null;
260                }
261            }
262
263            // see Functor::getType()
264            virtual inline Functor::Type::Enum getType() const override
265                { return Functor::Type::Member; }
266
267            /// Assigns an object-pointer to the functor which is used to execute a member-function.
268            inline void setObject(O* object)
269            {
270                if (this->bSafeMode_ && object != this->object_)
271                {
272                    this->unregisterObject(this->object_);
273                    this->registerObject(object);
274                }
275                this->object_ = object;
276            }
277            /// Returns the object-pointer.
278            inline O* getObject() const
279                { return this->object_; }
280
281            // see Functor::setRawObjectPointer()
282            virtual inline void setRawObjectPointer(void* object) override
283                { this->setObject((O*)object); }
284            // see Functor::getRawObjectPointer()
285            virtual inline void* getRawObjectPointer() const override
286                { return this->object_; }
287
288            // see Functor::setSafeMode()
289            virtual inline void setSafeMode(bool bSafeMode) override
290            {
291                if (bSafeMode == this->bSafeMode_)
292                    return;
293
294                this->bSafeMode_ = bSafeMode;
295
296                if (bSafeMode)
297                    this->registerObject(this->object_);
298                else
299                    this->unregisterObject(this->object_);
300            }
301
302        protected:
303            /// Casts the object and registers as destruction listener if the object is a Destroyable.
304            inline void registerObject(Destroyable* object)
305                { this->registerAsDestructionListener(object); }
306
307            inline void registerObject(void* object) {}
308
309            /// Casts the object and unregisters as destruction listener if the object is a Destroyable.
310            inline void unregisterObject(Destroyable* object)
311                { this->unregisterAsDestructionListener(object); }
312
313            inline void unregisterObject(void* object) {}
314
315            /// Will be called by Destroyable::~Destroyable() if the stored object is a Destroyable and deleted and the Functor is in safe mode.
316            virtual inline void objectDeleted() override
317                { this->object_ = nullptr; }
318
319            O* object_;     ///< The stored object-pointer, used to execute a member-function (or nullptr for static functions)
320            bool bSafeMode_; ///< If true, the functor is in safe mode and registers itself as listener at the object and changes the pointer to nullptr if the object is deleted
321    };
322
323    /// Specialization of FunctorMember with @a T = void.
324    template <>
325    class FunctorMember<void> : public Functor
326    {
327        public:
328            /// Constructor: Stores the object-pointer.
329            FunctorMember(void* object = nullptr) {}
330
331            /// Calls the function-pointer with up to five arguments and an object. In case of a static-function, the object can be nullptr. @return Returns the return-value of the function (if any; MultiType::Null otherwise)
332            virtual MultiType operator()(void* object, const MultiType& param1 = MultiType::Null, const MultiType& param2 = MultiType::Null, const MultiType& param3 = MultiType::Null, const MultiType& param4 = MultiType::Null, const MultiType& param5 = MultiType::Null) = 0;
333
334            // see Functor::operator()()
335            virtual MultiType operator()(const MultiType& param1 = MultiType::Null, const MultiType& param2 = MultiType::Null, const MultiType& param3 = MultiType::Null, const MultiType& param4 = MultiType::Null, const MultiType& param5 = MultiType::Null) override
336            {
337                return (*this)((void*)nullptr, param1, param2, param3, param4, param5);
338            }
339
340            // see Functor::getType()
341            virtual inline Functor::Type::Enum getType() const override
342                { return Functor::Type::Static; }
343
344            // see Functor::setRawObjectPointer()
345            virtual inline void setRawObjectPointer(void*) override
346                { orxout(internal_warning) << "Can't assign an object pointer to a static functor" << endl; }
347            // see Functor::getRawObjectPointer()
348            virtual inline void* getRawObjectPointer() const override
349                { return nullptr; }
350
351            // see Functor::setSafeMode()
352            virtual inline void setSafeMode(bool) override {}
353    };
354
355    /// FunctorStatic is just a typedef of FunctorMember with @a T = void.
356    typedef FunctorMember<void> FunctorStatic;
357
358    /**
359        @brief FunctorPointer is a child class of FunctorMember and expands it with a function-pointer.
360        @param F The type of the function-pointer
361        @param O The type of the function's class (or void if it's a static function)
362
363        The template FunctorPointer has an additional template parameter that defines the type
364        of the function-pointer. This can be handy if you want to get or set the function-pointer.
365        You can then use a static_cast to cast a Functor to FunctorPointer if you know the type
366        of the function-pointer.
367
368        However FunctorPointer is not aware of the types of the different parameters or the
369        return value.
370    */
371    template <class F, class O = void>
372    class FunctorPointer : public FunctorMember<O>
373    {
374        public:
375            /// Constructor: Initializes the base class and stores the function-pointer.
376            FunctorPointer(F functionPointer, O* object = nullptr) : FunctorMember<O>(object), functionPointer_(functionPointer) {}
377
378            /// Changes the function-pointer.
379            inline void setFunction(F functionPointer)
380                { this->functionPointer_ = functionPointer; }
381            /// Returns the function-pointer.
382            inline F getFunction() const
383                { return this->functionPointer_; }
384
385            // see Functor::getFullIdentifier()
386            virtual const std::type_info& getFullIdentifier() const override
387                { return typeid(F); }
388
389        protected:
390            F functionPointer_;     ///< The stored function-pointer
391    };
392
393    namespace detail
394    {
395        // Helper class to get the type of the function pointer with the given class, parameters, return-value, and constness
396        template <class R, class O, bool isconst, class... Params> struct FunctionPointer                            { typedef R (O::*Type)(Params...); };
397        template <class R, class O, class... Params>               struct FunctionPointer<R, O, true, Params...>     { typedef R (O::*Type)(Params...) const; };
398        template <class R, class... Params>                        struct FunctionPointer<R, void, false, Params...> { typedef R (*Type)(Params...); };
399
400        // Helper class, used to call a function-pointer with a given object and parameters and to return its return-value (if available)
401        template <class R, class O, bool isconst, class... Params> struct FunctorCaller                                 { template <class... UnusedParams> static inline MultiType call(typename detail::FunctionPointer<R, O, isconst, Params...>::Type       functionPointer, O* object, const Params&... parameters, const UnusedParams&...) { return (object->*functionPointer)(parameters...); } };
402        template <class O, bool isconst, class... Params>          struct FunctorCaller<void, O, isconst, Params...>    { template <class... UnusedParams> static inline MultiType call(typename detail::FunctionPointer<void, O, isconst, Params...>::Type    functionPointer, O* object, const Params&... parameters, const UnusedParams&...) { (object->*functionPointer)(parameters...); return MultiType::Null; } };
403        template <class R, bool isconst, class... Params>          struct FunctorCaller<R, void, isconst, Params...>    { template <class... UnusedParams> static inline MultiType call(typename detail::FunctionPointer<R, void, isconst, Params...>::Type    functionPointer, void*,     const Params&... parameters, const UnusedParams&...) { return (*functionPointer)(parameters...); } };
404        template <bool isconst, class... Params>                   struct FunctorCaller<void, void, isconst, Params...> { template <class... UnusedParams> static inline MultiType call(typename detail::FunctionPointer<void, void, isconst, Params...>::Type functionPointer, void*,     const Params&... parameters, const UnusedParams&...) { (*functionPointer)(parameters...); return MultiType::Null; } };
405
406        // Helper class to determine if a function has a returnvalue
407        template <class T>
408        struct FunctorHasReturnvalue
409        { enum { result = true }; };
410        template <>
411        struct FunctorHasReturnvalue<void>
412        { enum { result = false }; };
413
414        // Helper class to determine the N-th parameter of a variadic template (with 0 being the index of the first parameter)
415        template <int n, typename T = void, typename... Other>
416        struct GetNthParamType
417        { typedef typename GetNthParamType<n - 1, Other...>::Type Type; };
418        template <typename T, typename... Other>
419        struct GetNthParamType<0, T, Other...>
420        { typedef T Type; };
421
422        //Helper structs to deduce the first N types of a parameter pack
423        template<class... Types> struct type_list {};
424
425        template <class T1, class... AllTypes>
426        struct make_type_list_helper
427        {
428            template <std::size_t N, class... Types>
429            struct make_type_list_impl : make_type_list_helper<AllTypes...>::template make_type_list_impl<N - 1, Types..., T1> {};
430
431            template <class... Types>
432            struct make_type_list_impl<1u, Types...> : type_list<Types..., T1> {};
433        };
434
435        template <class T1>
436        struct make_type_list_helper<T1>
437        {
438            template <std::size_t N, class... Types>
439            struct make_type_list_impl : type_list<Types..., T1> {};
440        };
441
442        template <std::size_t N, class... Types>
443        struct make_type_list : make_type_list_helper<Types...>::template make_type_list_impl<N> {};
444
445        template <class... Types>
446        struct make_type_list<0u, Types...> : type_list<> {};
447
448        template <std::size_t N>
449        struct make_type_list<N> : type_list<> {};
450
451        template <>
452        struct make_type_list<0u> : type_list<> {};
453    }
454
455    /**
456        @brief FunctorTemplate is a child class of FunctorPointer and implements all functions
457        that need to know the exact types of the parameters, return-value, and class.
458
459        @param R The type of the return-value of the function
460        @param O The class of the function
461        @param isconst True if the function is a const member-function
462        @param Params The types of the parameters
463
464        This template has many parameters and is usually not used directly. It is created by
465        createFunctor(), but only the base-classes Functor, FunctorMember, and FunctorPointer
466        are used directly. It implements all the virtual functions that are declared by its
467        base classes.
468
469        All template arguments can be void.
470    */
471    template <class R, class O, bool isconst, class... Params>
472    class FunctorTemplate : public FunctorPointer<typename detail::FunctionPointer<R, O, isconst, Params...>::Type, O>
473    {
474        static_assert(sizeof...(Params) <= 5, "Only up to 5 parameters are supported");
475
476        public:
477            /// Constructor: Initializes the base class.
478            FunctorTemplate(typename detail::FunctionPointer<R, O, isconst, Params...>::Type functionPointer, O* object = nullptr) : FunctorPointer<typename detail::FunctionPointer<R, O, isconst, Params...>::Type, O>(functionPointer, object) {}
479
480            // see FunctorMember::operator()()
481            virtual MultiType operator()(O* object, const MultiType& param1 = MultiType::Null, const MultiType& param2 = MultiType::Null, const MultiType& param3 = MultiType::Null, const MultiType& param4 = MultiType::Null, const MultiType& param5 = MultiType::Null) override
482            {
483                return detail::FunctorCaller<R, O, isconst, Params...>::call(this->functionPointer_, object, param1, param2, param3, param4, param5);
484            }
485
486            // see Functor::clone()
487            virtual FunctorPtr clone() override
488            {
489                return std::make_shared<FunctorTemplate>(*this);
490            }
491
492            // see Functor::evaluateArgument()
493            virtual void evaluateArgument(unsigned int index, MultiType& argument) const override
494            {
495                switch (index)
496                {
497                    case 0: argument.convert<typename detail::GetNthParamType<0, Params...>::Type>(); break;
498                    case 1: argument.convert<typename detail::GetNthParamType<1, Params...>::Type>(); break;
499                    case 2: argument.convert<typename detail::GetNthParamType<2, Params...>::Type>(); break;
500                    case 3: argument.convert<typename detail::GetNthParamType<3, Params...>::Type>(); break;
501                    case 4: argument.convert<typename detail::GetNthParamType<4, Params...>::Type>(); break;
502                }
503            }
504
505            // see Functor::getParamCount()
506            virtual unsigned int getParamCount() const override
507            {
508                return sizeof...(Params);
509            }
510
511            // see Functor::hasReturnvalue()
512            virtual bool hasReturnvalue() const override
513            {
514                return detail::FunctorHasReturnvalue<R>::result;
515            }
516
517            // see Functor::getTypenameParam()
518            virtual std::string getTypenameParam(unsigned int index) const override
519            {
520                switch (index)
521                {
522                    case 0:  return typeToString<typename detail::GetNthParamType<0, Params...>::Type>();
523                    case 1:  return typeToString<typename detail::GetNthParamType<1, Params...>::Type>();
524                    case 2:  return typeToString<typename detail::GetNthParamType<2, Params...>::Type>();
525                    case 3:  return typeToString<typename detail::GetNthParamType<3, Params...>::Type>();
526                    case 4:  return typeToString<typename detail::GetNthParamType<4, Params...>::Type>();
527                    default: return "";
528                }
529            }
530
531            // see Functor::getTypenameReturnvalue()
532            virtual std::string getTypenameReturnvalue() const override
533            {
534                return typeToString<R>();
535            }
536
537            // see Functor::getHeaderIdentifier()
538            virtual const std::type_info& getHeaderIdentifier() const override
539            {
540                return typeid(typename detail::FunctionPointer<R, void, false, Params...>::Type);
541            }
542
543            // see Functor::getHeaderIdentifier(unsigned int)
544            virtual const std::type_info& getHeaderIdentifier(unsigned int params) const override
545            {
546                switch (params)
547                {
548                    case 0:  return this->getTypelistIdentifier(detail::make_type_list<0, Params...>{});
549                    case 1:  return this->getTypelistIdentifier(detail::make_type_list<1, Params...>{});
550                    case 2:  return this->getTypelistIdentifier(detail::make_type_list<2, Params...>{});
551                    case 3:  return this->getTypelistIdentifier(detail::make_type_list<3, Params...>{});
552                    case 4:  return this->getTypelistIdentifier(detail::make_type_list<4, Params...>{});
553                    default: return this->getTypelistIdentifier(detail::make_type_list<5, Params...>{});
554                }
555            }
556
557    private:
558            ///Helper function that deduces a parameter pack of types and returns the corresponding identifier
559            template<class... Types>
560            const std::type_info& getTypelistIdentifier(detail::type_list<Types...>) const
561            {
562                return typeid(typename detail::FunctionPointer<R, void, false, Types...>::Type);
563            }
564    };
565
566
567    /**
568    @brief FunctorCallable is a child class of FunctorTemplate. It stores a callable
569    object (e.g. a lambda or a class with operator()) inside and acts like any
570    other functor. Note that it stores a \em copy of the object, not a reference or a pointer.
571    Take care that this functor does not outlive objects that have been captured by reference
572    in a lambda.
573
574    @param F The type of the callable object
575    @param R The type of the return-value of the function
576    @param isconst True if operator() is const
577    @param Params The types of the parameters
578
579    This template can not be used directly when using lambdas - the type of a lambda
580    is not specified. It can only really be used through the base-class Functor.
581    */
582    template <class F, class R, bool isconst, class... Params>
583    class FunctorCallable : public FunctorTemplate<R, F, isconst, Params...>
584    {
585    public:
586        FunctorCallable(const F& obj): FunctorTemplate<R, F, isconst, Params...>(&F::operator(), &obj_)
587            , obj_(obj)
588        {}
589
590    private:
591        F obj_; ///< The callable object
592    };
593
594    namespace detail
595    {
596        //Helper functions to deduce types and constness of operator() and return the correct FunctorCallable
597        template <class F, class R, class... Params> inline FunctorMemberPtr<F> callableHelper(const F& obj, R(F::*func)(Params...) const) { return std::make_shared<FunctorCallable<F, R, true, Params...>>(obj); }
598        template <class F, class R, class... Params> inline FunctorMemberPtr<F> callableHelper(const F& obj, R(F::*func)(Params...)) { return std::make_shared<FunctorCallable<F, R, false, Params...>>(obj); }
599    }
600
601    template <class R, class O, class OO, class... Params> inline FunctorMemberPtr<O> createFunctor(R (O::*functionPointer)(Params...),       OO* object) { return std::make_shared<FunctorTemplate<R, O, false, Params...>>(functionPointer, object); } ///< Creates a new FunctorMember with the given function-pointer and an assigned object
602    template <class R, class O, class OO, class... Params> inline FunctorMemberPtr<O> createFunctor(R (O::*functionPointer)(Params...) const, OO* object) { return std::make_shared<FunctorTemplate<R, O, true,  Params...>>(functionPointer, object); } ///< Creates a new FunctorMember with the given function-pointer and an assigned object
603
604    template <class R, class O, class... Params> inline FunctorMemberPtr<O> createFunctor(R (O::*functionPointer)(Params...))       { return std::make_shared<FunctorTemplate<R, O, false, Params...>>(functionPointer); } ///< Creates a new FunctorMember with the given function-pointer
605    template <class R, class O, class... Params> inline FunctorMemberPtr<O> createFunctor(R (O::*functionPointer)(Params...) const) { return std::make_shared<FunctorTemplate<R, O, true,  Params...>>(functionPointer); } ///< Creates a new FunctorMember with the given function-pointer
606
607    template <class R, class... Params> inline FunctorStaticPtr createFunctor(R (*functionPointer)(Params...)) { return std::make_shared<FunctorTemplate<R, void, false, Params...>>(functionPointer); } ///< Creates a new FunctorStatic with the given function-pointer
608   
609    template <class F> inline FunctorMemberPtr<F> createFunctor(const F& obj) { return detail::callableHelper(obj, &F::operator()); } ///< Creates a new Functor with a callable object
610}
611
612#endif /* _Functor_H__ */
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