🚀 go-pugleaf

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>>         const int N = 4;
>>         void* p = malloc(N * sizeof(CHoge));
>>         if (p) {
>>             CHoge* vips = new(p) CHoge[N];
>>             vector< hitman<CHoge> > request(vips, vips + N);


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    #include <iostream>
    #include <vector>
    #include <new>
    using namespace std;
    
    template <class T> class hitman
    {
    public:
        typedef std::vector<const T*> targets;
    
        hitman(const T* p, const size_t N) : t()
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        {
            try { t.resize(N); }
            catch (...) {
                for (size_t i = 0; i < N; i++) p[i].~T();
                throw;
            }
            for (size_t i = 0; i < N; i++) t[i] = p + i;
        }
    
        ~hitman() { for (size_t i = 0; i < t.size(); i++) t[i]->~T(); }
    private:
        targets t;
    };
    
    class CHoge
    {
    public:
        CHoge() { cerr << "CHoge: Ogyaaa!!" << endl; }
        ~CHoge() { cerr << "CHoge: Ugyaaa!!" << endl; }
    };
    
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    // void* operator new[](const size_t, void* p) throw() { return p; }
    
    int main()
    {
        try {
            const size_t N = 4;
            void* p = malloc(N * sizeof(CHoge));
            if (p) {
                CHoge* vips = new(p) CHoge[N];
                hitman<CHoge> request(vips, N);
                // ...
            }
            return 0;
        }
        catch (...) { exit(1); }
    }

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--
Email: okahisa@cs.ehime-u.ac.jp