Conversation operator as a lval?

[Matt]

Does C++ provide a means to use a conversion operator as a lval?

ie, I want:

class superInt
{
public:
operator int() { return this->value; }
private:
int value;
};

....to instead be this:

class superInt
{
public:
int& operator int() { return this->value; }
private:
int value;
};

....which will not compile.

I suspect the C++ language designers avoided this on purpose, but I
thought I would ask here just in case there is a means to do this (in
some other way then I present above).

Such a thing would save me time re-writing a bunch of overloaded
operators for superInt (among other things).

-Matt

 

[Victor Bazarov]

Does C++ provide a means to use a conversion operator as a lval?\
Sure.

ie, I want:

class superInt
{
public:
operator int() { return this->value; }

Should probably be

operator int() const { return this->value; }

private:
int value;
};

...to instead be this:

class superInt
{
public:
int& operator int() { return this->value; }

operator int&() { return this->value; }

private:
int value;
};

...which will not compile.

Of course.

I suspect the C++ language designers avoided this on purpose,

No, they didn't.

but I
thought I would ask here just in case there is a means to do this (in
some other way then I present above).

Very good choice.

Such a thing would save me time re-writing a bunch of overloaded
operators for superInt (among other things).

But it is rather dangerous. Be careful.

Victor

 

[Matt]

operator int&() { return this->value; }

Great, I'm glad I asked here. Thanks!

But it is rather dangerous. Be careful.

Yes, I can see where it can be quite dangerous. I think I will avoid
it whenever I can...especially since I've already written all my
overloaded operators for the task at hand.

-Matt