c++ - If QList instance is const, does it mean each element is constant? -


the following code fails compile:

void func(const qlist<int>& list){   auto& elem = list[0]; }

the problem cannot bind const element non-const reference. following code works:

const auto& elem = list[0];

can explain why passing list const makes element const?

can explain why passing list const makes element const?

this semantics standard containers following. here's reason can see:

const int arr1 = {10, 20}; arr1[0] = 40; // error. elements of arr1 cannot modified.  const std::vector<int> arr2 = {10, 20}; arr2[0] = 40; // same semantics. error. elements of arr2 cannot modified.

extending logic qlist, elements of qlist const if qlist const.


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