How to initialize the reference member variable of a class?
c++, class-members, oop
Solution
That is because references can only be initialized in the initializer list. Use
Test (int &x) : t(x) {}
To explain: The reference can only be set once, the place where this happens is the initializer list. After that is done, you can not set the reference, but only assign values to the referenced instance. Your code means, you tried to assign something to a referenced instance but the reference was never initialized, hence it's not referencing any instance of `int` and you get the error.
Problem
Consider the following code C++: ``` #include<iostream> using namespace std; class Test { int &t; public: Test (int &x) { t = x; } int getT() { return t; } }; int main() { int x = 20; Test t1(x); cout << t1.getT() << " "; x = 30; cout << t1.getT() << endl; return 0; } ``` It is showing the following error while using gcc compiler ``` est.cpp: In constructor ‘Test::Test(int&)’: est.cpp:8:5: error: uninitialized reference member ‘Test::t’ [-fpermissive] ``` Why doesn't the compiler directly call the Constructor?