In reply to http://stackoverflow.com/a/18803611/245869 "For a value type Foo, why does a shared_ptr<const Foo> act like a value type even though it is a pointer type?"

0_main.cpp

#include <iostream>
#include <memory>

#include "Foo.hpp"
#include "Bar.hpp"


int main()
{
	auto bar = Bar{};
	std::shared_ptr<const Foo> foo = bar.foo();

	std::cout << "Foo's num: " << foo->num() << std::endl;

	bar.doSomething();

	std::cout << "Foo's num: " << foo->num() << std::endl;
	
	// Output:
	// Foo's num: 0
	// Foo's num: 5
}

Bar.hpp

class Bar {

public:
	std::shared_ptr<const Foo> foo() const
	{
		return foo_;
	}

	void doSomething()
	{
		foo_->setNum(5);
	}

private:
	std::shared_ptr<Foo> foo_{std::make_shared<Foo>()};

};

Foo.hpp

class Foo {

public:
	int num() const
	{
		return num_;
	}

	void setNum( int num )
	{
		num_ = num;
	}

private:
	int num_{0};

};