Privacy and Inheritance

[Erik Max Francis]

Eric Brunel wrote:

> I just meant that Python has no way of enforcing "protectedness", as
> leading double underscores (kind of) enforce privateness. As you say,
> using
> a single leading underscore in protected attribute names is merely a
> convention, even if it's a strong one: Python won't prevent any use of
> the
> attribute, neither from sub-classes, nor from the "outside world".
> Anybody
> not knowing the convention can use these attributes in any way without
> any
> problem.

That's right.  Python takes the approach that "We're all adults here,"
and presumes that people will behave.  In many languages the concept of
restricted access can be circumvented in varying ways with increasing
levels of ugliness, so you can think of restricted access as really a
hint (albeit a very strong one in those languages where it is very
awkward).

Python just leaves these things at the hint level (with the exception of
double underscore name mangling, which is a fairly recent addition).

-- 
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