c++ - error: invalid initialization of reference of type 'int&' from expression of type 'const int' -


this unrelated question code in this question, regarding following template function.

template <class t> class object : public container { public: t& object; object(const t& obj) : object(obj) {} };

this code calls constructor:

template <class t> void array::add_element(const t& element) { vec.push_back(new object<t>(element)); }

this code compiles fine, add line in main calls it:

array array; int = 3; array.add_element(i);

i compiler warning: error: invalid initialization of reference of type 'int&' expression of type 'const int'.

what about? passed int in. shouldn't automatically turned const int& me? why compiler complaining?

obj const reference. object non-const reference.

you can't initialize non-const reference const reference, because doing defeat purpose of having const reference in first place.

if want instance of object able modify int that's passed constructor, constructor should take non-const reference. if don't, data member should const reference.

in case, storing trouble if use new allocate objects have references data members. it's your problem ensure delete object before i goes out of scope (or anyway, ensure object doesn't use member object after i goes out of scope.


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