Using + operator without memory leak?

Question

So this code is as follows:

const String String::operator+ (const String& rhs)  
{  
    String tmp;  
    tmp.Set(this->mString);  
    tmp.Append(rhs.mString);  
    return tmp;  
}  

This, of course, pushes String onto the stack and gets deleted and returns garbage. And putting it in a heap will be a memory leak. So how do I do this?

Answer 1

Your solution does not return garbage if you have a working constructor - the String object is tmpcopied to the result object before it is destroyed at the end of the block.

You can do it better by replacing

String tmp;
tmp.Set(this->mString);

from

String tmp(*this);

(for this you need a properly working copy constructor, but you need it anyway for your operator return)

Answer 2

, , . , .

Answer 3

std::string,

( )

( String , )

Answer 4

. String "const String".