import concerns (was Re: Historical language survey)

[Sean Kelly]

Walter Bright wrote:
> Derek Parnell wrote:
>> I'm sorry Walter but I don't give newt's fart about C++. If I wanted 
>> to code under the rules of C++, I'd use C++. You have changed 
>> (improved) many of the C++ rules in D, so why not get this one right too?
> 
> I agree that D exists to fix broken rules in C++, but we need to 
> understand the rationale for why they are the way they are in C++, else 
> we run the risk of making a severe error. I don't recall why the access 
> rules are the way they are in C++, but I do know they weren't don't that 
> way for backwards compatibility.

Please see my post here:

http://www.digitalmars.com/drn-bin/wwwnews?digitalmars.D/39072

According to Daveed Vandevoorde:

    The fact that private members are inaccessible but not invisible
    regularly surprises incidental programmers. Like macros, seemingly
    unrelated declarations interfere with subsequent code. Unfortunately,
    there are good reasons for this state of affair: Without it, private
    out-of-class member declarations become impractical to parse in the
    general case.

So assuming he's right (I couldn't find the minutes of the original 
meetings to back up his claim) then the decision was made fore purely 
technical reasons, and reasons that don't seem to apply to D because of 
the different meaning of 'private'.  Daveed goes on to say:

    Module namespaces appear to be an ideal boundary for making the
    private member fully invisible: Within the module the implementer has
    full control over naming conventions and can therefore easily avoid
    interference, while outside the module the client will never
    have to implement private members. (Note that this also addresses the
    concerns of N1602 "Class Scope Using Declarations & private Members"
    by Francis Glassborow; the extension proposed therein is then no
    longer needed.)

(note that this is the proposal for modules in C++)

I know you've read the proposal, but it's available here for those who 
don't want to follow my link above:

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1964.pdf


Sean