Re: Encapsulation in Ada vs. C++ (Was Re: Ichibah [sic] ...)

[magnus@lglsun.epfl.ch (Magnus Kempe)]

dag@control.lth.se (Dag Bruck) writes:
: A [C++] class grants friendship to other functions or classes, which means
: that the author of a class controls who gets access to the private
: members of the class.  You cannot grant yourself access to any random
: class.

If your class Foo grants "friendship" to a function/class Bar, _anyone_
can write such a function/class and, having granted itself "friendliness",
will have access to the internals of Foo.

To repeat: contrary to Ada, C++ does not provide a safe means to create
subprograms acting on parameters of two or more types (classes).  In
C++, either you write an unsafe class because the language lacks the
concept of a module, or you twist around with .h files and say good-bye
to limited, separate recompilations.

-- 
Magnus Kempe                "No nation was ever drunk when wine was cheap."
magnus@lglsun.epfl.ch                                   -- Thomas Jefferson