C++ 11 std::unique_ptr related compiling error

Falconapollo

I'm stuck here on how to compile the following code, i need to put a struct which contains std::unique_ptr into std::map, but i always get the error message, anybody can help me?

Quote:

e:\console.cpp(21): error C2248: 'std::unique_ptr<_Ty>::unique_ptr' : cannot access private member declared in class 'std::unique_ptr<_Ty>' 1> with 1> [ 1> _Ty=int 1> ] 1> d:\programfiles\vs 2010\vc\include\memory(2347) : see declaration of 'std::unique_ptr<_Ty>::unique_ptr' 1> with 1> [ 1> _Ty=int 1> ] 1> This diagnostic occurred in the compiler generated function 'Baa::Baa(const Baa &)' 1> 1>Build FAILED. 1> 1>Time Elapsed 00:00:01.28 ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

here is my code:

#include
#include
#include
#include

struct Baa {
std::unique_ptr x;

Baa() {
}

Baa(Baa&& o)
{
	x = std::move(o.x);
}
Baa operator = (Baa&& param)
{
	x = std::move(param.x);
	return \*this;
}

};

int main()
{
std::map sheep;
Baa ba;
sheep[0] = ba;
}

yufengzjj

which compiler you use? with what options?

Theo Buys

Your don't initialize x

vickoza

the problem is simple. The code

sheep[0] = ba;

should be

sheep[0] = std::move(ba);

Your first approach used the copy constructor to copy the unique_ptr this defeats the purpose unique_ptr. Also another issue is:

Baa operator = (Baa&& param)

should be

Baa& operator = (Baa&& param)