Essential Books

FinallyScopeExit

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For cases when we don’t want to write special classes to handle some resource, we may write a generic class: 

template<typename Function>
class Finally final
{
public:
    explicit Finally(Function f) : f(std::move(f)) {}
    ~Finally() { f(); } // (1) See below

    Finally(const Finally&) = delete;
    Finally(Finally&&) = default;
    Finally& operator =(const Finally&) = delete;
    Finally& operator =(Finally&&) = delete;
private:
    Function f;
};
// Execute the function f when the returned object goes out of scope.
template<typename Function>
auto onExit(Function &&f) { return Finally<std::decay_t<Function>>{std::forward<Function>(f)}; }

And its example usage 

void foo(std::vector<int>& v, int i)
{
    // ...

    v[i] += 42;
    auto autoRollBackChange = onExit([&](){ v[i] -= 42; });

    // ... code as recursive call `foo(v, i + 1)`
}

Note (1): Some discussion about destructor definition has to be considered to handle exception:

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RAII:
* RAII Resource Acquisition Is Initialization
* Locking
* FinallyScopeExit
* ScopeSuccess C++ 17
* ScopeFail C++ 17
Table Of Contents
0 Getting started
1 Literals
2 Basic type keywords
3 Operator precedence
4 Floating point arithmetic
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33 std::function
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35 std::iomanip
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42 Returning multiple values from a function
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91 Date and time with std::chrono
92 Trailing return type
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94 Common compile linker errors
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99 One definition rule
100 Unspecified behavio
101 Argument dependent name lookup
102 Attributes
103 Internationalization
104 Profiling
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106 Non-static member functions
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110 C++ vs. C++ 11 vs C++ 17
111 Inline functions
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131 Layout of object types
132 C incompatibilities
133 Optimization
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135 Thread synchronization
136 Debugging
137 Futures and promises
138 More undefined behaviors
139 Mutexes
140 Recursive mutex
141 Unit testing
142 decltype
143 Digit separators
144 C++ Containers
145 Arithmetic meta-programming
146 Contributors