c++ Passing unique_ptr as a reference to another function

Question

This seens to be basic, but I need some help.

I have a sample class:

class myClass {
 int a;
 int b;
}

Then a factory:

class myFactory {
 std::unique_ptr<myClass> getInstance()
 {
 return std::unique_ptr<myClass>(new myClass);
 }
}

Then I have several funtions that will receive myClass by reference:

doSomething (myClass& instance)
{
 instance.a = 1;
 instance.b = 2;
}

And the main code, where I ́m stuck:

main()
{
 myFactory factory;
 std::unique_ptr<myClass> instance = factory.getInstance();
 doSomething(instance.get()) <--- This is not compiling
}

How do I correctly call the doSomething() function passing the instance as a reference as expected ?

Note that doSomething() will modify instance data...

• davidhigh: get() returns a pointer, your function takes a reference.
• user4842163: operator* to access the pointee, just like your plain old raw pointer.
• Sander De Dycker: you might be interested in std::make_unique (as an alternative to your factory eg.)

Answer 1

std::unique_ptr<T>::get returns the underlying raw pointer, not the pointee. unique_ptr provides operator* for directly getting at the instance.

doSomething(*instance);