Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> He's saying that putting "private:" before the variables in a class 
>> declaration is equivalent to naming private variables with an underscore. In 
>> the first case, the compiler warns you if you use a private variable by 
>> mistake.
> 
>   Could you give a concrete example of a compiler, of any OO language,
> which will only *warn* (rather than give an error message) if you try to
> access a member variable specifically marked as private from the outside?

Sure. C# or Java. You get this warning that says "this won't compile."  So 
you use the reflection libraries instead, and it compiles. The compiler 
hasn't stopped you from accessing the private variable. It just stopped you 
from trivially accidentally accessing the private variable. (Python doesn't 
even prevent you from trivially accessing the private variable, but in 
practice it isn't a problem.)

I know what you're asking. I'm asking you to look at it from a slightly 
different point of view. Take a more general approach to what it means to 
get "a warning" than the usual "the compiler issues warnings and errors, and 
nothing else is meaningful."

Another example is, as I've been saying, C++. The compiler warns (and won't 
compile) if you access the private variable by name, but not if you 
intentionally or accidentally access the private variable by address. Again, 
I understand what you're saying, and I'm asking you to also try to 
understand what I'm saying, instead of thinking I'm only saying it to annoy 
you. This is really how I think about programming - what do I know, and what 
might be broken. That's why I dislike unsafe languages with undefined behavior.

-- 
   Darren New, San Diego CA, USA (PST)
   My fortune cookie said, "You will soon be
   unable to read this, even at arm's length."

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