Warp wrote:
>   It seems that in your quest to belittle "unsafe languages" you have taken
> some obscure definition of a term somewhere, 

Not at all. I'm simply explaining why safety is important to encapsulation.

Do you think Python encapsulates data?  If so, then C++ does too.

If you think Python insufficiently protects its data, then neither does any 
unsafe-by-default language.

>   Nowhere do I see anything related to what you wrote.

The whole "information hiding" bit, for one.

"""
Under this definition, encapsulation means that the internal representation 
of an object is generally hidden from view outside of the object's definition.
"""

C++ fails this. Internal representation is in the header file. But that's 
not what I'm talking about.

"""
Typically, only the object's own methods can directly inspect or manipulate 
its fields.
"""

All unsafe languages fail this.  (Lots of safe languages do too, with 
appropriate declarations of their unsafeness.)

"""
Hiding the internals of the object protects its integrity by preventing 
users from setting the internal data of the component into an invalid or 
inconsistent state.
"""

Unsafe languages fail at this. Either that, or you have never ever 
encountered a wild-pointer bug. The fact that you don't frequently violate 
encapsulation doesn't mean that encapsulation is enforced, any more than the 
fact that people don't usually screw around with the internals of Python 
instances doesn't mean Python has good encapsulation in that sense.

In theory, yes, if you don't violate the language mechanisms, then C++ 
provides encapsulation. In practice, it doesn't, because when some value in 
your object is randomly changed by a bug in some code running in other 
thread, you're fairly well screwed in terms of figuring out the 
encapsulation.  That is, pretty much, the difference between safe languages 
and unsafe languages: Safe languages *enforce* encapsulation. (And again, 
most safe languages allow you to circumvent that by dropping into an unsafe 
subset, but some don't.)

-- 
Darren New, San Diego CA, USA (PST)
   The question in today's corporate environment is not
   so much "what color is your parachute?" as it is
   "what color is your nose?"

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