Quick Q: When should I make explicit use of the `this` pointer?
Quick A: to disambiguate.
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When should I make explicit use of the `this` pointer?
Usually, you do not have to, this-> is implied.
Sometimes, there is a name ambiguity, where it can be used to disambiguate class members and local variables. However, here is a completely different case where this-> is explicitly required.
Consider the following code: template<class T> struct A { int i; }; template<class T> struct B : A<T> { int foo() { return this->i; } }; int main() { B<int> b; b.foo(); }If you omit this->, the compiler does not know how to treat i, since it may or may not exist in all instantiations of A. In order to tell it that i is indeed a member of A<T>, for any T, the this-> prefix is required.
Note: it is possible to still omit this-> prefix by using:
template<class T> struct B : A<T> { using A<T>::i; // explicitly refer to a variable in the base class int foo() { return i; // i is now known to exist } };
