Re: member variable of STL string class

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"George" wrote:
I have tried the code, no warning and output is
"msdn.microsoft.com", what is wrong?

string foo()
{
string b;
...
return b;
}


In the code above you do not return a reference to the local
variable `b'. Instead, you return a copy of `b'. It is OK to retun
copies of local objects from a function.

However, you have other problem:

int main()
{
string& s1 = foo();

cout << s1 << endl;

return 0;
}

You bind a non-constant reference to a temporary copy of an
object. This is unsafe and conflicts with C++ Standard. Compiler
rightfully warns you with C4239 warning about this. If you don't
see this warning, then go to project settings and select warning
level 4 in C/C++ category.

Alex


.

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