#include #include #include #include #include using namespace std; // used for indexing struct Index { Index(size_t i=0) :idx(i) {} operator size_t() const {return idx;} operator size_t() {return idx;} size_t idx; }; // overload comma operator to return // a pair of Index which will be used // as an argument to // subscript operator[] of an Array // class pair operator, (Index const& lhs, Index const& rhs) { return make_pair(lhs,rhs); } // Generic Array class template class Array { using iterator = T*; public: Array(initializer_list l) : Array(l.size()) { copy(std::begin(l),std::end(l), begin()); } Array(size_t sz=1) : m_ptr{new T[sz]}, m_size{sz} {} T& operator[](size_t idx) { return m_ptr[idx]; } T operator[](size_t idx) const { return m_ptr[idx]; } Array operator[]( pair const& idx)const { Array out(idx.second-idx.first); copy(begin()+idx.first, begin()+idx.second, std::begin(out)); return out; } size_t size() const { return m_size; } T* begin() { return m_ptr;} T const* begin() const { return m_ptr; } T* end() { return m_ptr+m_size; } T const* end() const { return m_ptr+m_size; } Array operator = (Array const& rhs) { if(this != &rhs) { delete [] m_ptr; m_ptr = new T[rhs.size()]; copy(std::begin(rhs), std::end(rhs), begin()); m_size = rhs.size(); } return *this; } private: T* m_ptr; size_t m_size; }; // Print helper auto Print = [](auto const& Obj) { for(auto const& e : Obj) { cout << e << " "; } cout << endl << endl; }; int main() { Array arr{0,1,2,3,4,5,6,7,8,9}; cout << "Integer array:\n"; Print(arr); // new integer array from sliced // array Array narr = arr[{3,8}]; cout << "sliced array containing elements 3 to 8 from original array:\n"; Print(narr); Array sarr{"zero","one","two", "three", "four", "five","six","seven", "eight","nine","ten"}; cout << "String array:\n"; Print(sarr); // slice the array cout << "element 2 to 7 in string array are:\n"; Print(sarr[{2,7}]); // reassign the string array sarr = {"one","one","one"}; cout << "string array now becomes:\n"; Print(sarr); }

comma_overloading_with_array_slicing.cpp