1 /* 2 * libjingle 3 * Copyright 2012 Google Inc. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright notice, 9 * this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 17 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO 19 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 // To generate bind.h from bind.h.pump, execute: 29 // /home/build/google3/third_party/gtest/scripts/pump.py bind.h.pump 30 31 // Bind() is an overloaded function that converts method calls into function 32 // objects (aka functors). It captures any arguments to the method by value 33 // when Bind is called, producing a stateful, nullary function object. Care 34 // should be taken about the lifetime of objects captured by Bind(); the 35 // returned functor knows nothing about the lifetime of the method's object or 36 // any arguments passed by pointer, and calling the functor with a destroyed 37 // object will surely do bad things. 38 // 39 // Example usage: 40 // struct Foo { 41 // int Test1() { return 42; } 42 // int Test2() const { return 52; } 43 // int Test3(int x) { return x*x; } 44 // float Test4(int x, float y) { return x + y; } 45 // }; 46 // 47 // int main() { 48 // Foo foo; 49 // cout << talk_base::Bind(&Foo::Test1, &foo)() << endl; 50 // cout << talk_base::Bind(&Foo::Test2, &foo)() << endl; 51 // cout << talk_base::Bind(&Foo::Test3, &foo, 3)() << endl; 52 // cout << talk_base::Bind(&Foo::Test4, &foo, 7, 8.5f)() << endl; 53 // } 54 55 #ifndef TALK_BASE_BIND_H_ 56 #define TALK_BASE_BIND_H_ 57 58 #define NONAME 59 60 namespace talk_base { 61 namespace detail { 62 // This is needed because the template parameters in Bind can't be resolved 63 // if they're used both as parameters of the function pointer type and as 64 // parameters to Bind itself: the function pointer parameters are exact 65 // matches to the function prototype, but the parameters to bind have 66 // references stripped. This trick allows the compiler to dictate the Bind 67 // parameter types rather than deduce them. 68 template <class T> struct identity { typedef T type; }; 69 } // namespace detail 70 71 $var n = 5 72 $range i 0..n 73 $for i [[ 74 $range j 1..i 75 76 template <class ObjectT, class MethodT, class R$for j [[, 77 class P$j]]> 78 class MethodFunctor$i { 79 public: 80 MethodFunctor$i(MethodT method, ObjectT* object$for j [[, 81 P$j p$j]]) 82 : method_(method), object_(object)$for j [[, 83 p$(j)_(p$j)]] {} 84 R operator()() const { 85 return (object_->*method_)($for j , [[p$(j)_]]); } 86 private: 87 MethodT method_; 88 ObjectT* object_;$for j [[ 89 90 P$j p$(j)_;]] 91 92 }; 93 94 template <class FunctorT, class R$for j [[, 95 class P$j]]> 96 class Functor$i { 97 public: 98 $if i == 0 [[explicit ]] 99 Functor$i(const FunctorT& functor$for j [[, P$j p$j]]) 100 : functor_(functor)$for j [[, 101 p$(j)_(p$j)]] {} 102 R operator()() const { 103 return functor_($for j , [[p$(j)_]]); } 104 private: 105 FunctorT functor_;$for j [[ 106 107 P$j p$(j)_;]] 108 109 }; 110 111 112 #define FP_T(x) R (ObjectT::*x)($for j , [[P$j]]) 113 114 template <class ObjectT, class R$for j [[, 115 class P$j]]> 116 MethodFunctor$i<ObjectT, FP_T(NONAME), R$for j [[, P$j]]> 117 Bind(FP_T(method), ObjectT* object$for j [[, 118 typename detail::identity<P$j>::type p$j]]) { 119 return MethodFunctor$i<ObjectT, FP_T(NONAME), R$for j [[, P$j]]>( 120 method, object$for j [[, p$j]]); 121 } 122 123 #undef FP_T 124 #define FP_T(x) R (ObjectT::*x)($for j , [[P$j]]) const 125 126 template <class ObjectT, class R$for j [[, 127 class P$j]]> 128 MethodFunctor$i<const ObjectT, FP_T(NONAME), R$for j [[, P$j]]> 129 Bind(FP_T(method), const ObjectT* object$for j [[, 130 typename detail::identity<P$j>::type p$j]]) { 131 return MethodFunctor$i<const ObjectT, FP_T(NONAME), R$for j [[, P$j]]>( 132 method, object$for j [[, p$j]]); 133 } 134 135 #undef FP_T 136 #define FP_T(x) R (*x)($for j , [[P$j]]) 137 138 template <class R$for j [[, 139 class P$j]]> 140 Functor$i<FP_T(NONAME), R$for j [[, P$j]]> 141 Bind(FP_T(function)$for j [[, 142 typename detail::identity<P$j>::type p$j]]) { 143 return Functor$i<FP_T(NONAME), R$for j [[, P$j]]>( 144 function$for j [[, p$j]]); 145 } 146 147 #undef FP_T 148 149 ]] 150 151 } // namespace talk_base 152 153 #undef NONAME 154 155 #endif // TALK_BASE_BIND_H_ 156
