Paul Paul - 4 months ago 46
C++ Question

typesafe typedef in C++

I would like to use something like typedef in my C++ programs to enhance type safety.

As an example, suppose I have two functions

void function1(unsigned idOfType1);
void function2(unsigned idOfType2);

then I can mistakenly pass idOfType2 to function1 and vice versa. I want the compiler to give me an error in this case. I am aware that I could wrap these unsigned in a struct, but then I'd have to give provide a field name and use
to access them, which is slightly inconvenient. Is there a good way around this?

Edit: As far as I know
will not work for this purpose as it is just a shorthand for a type and will not be used for type checking.


As you say, a typedef won't help you here. I can't think of a better way immediately, however if you go with your wrapping in a struct/class option you could use a conversion operator to eliminate the member method or function call.

For example:

struct WrappedType
    operator type()
         return _value;

    type _value;  

I'm not saying this is the way to do it mind you ;-)