Re: private inheritance vs containment

In article <f3d8g6$o8l$1@news.Stanford.EDU>, Seungbeom Kim
<musiphil@bawi.org> wrote:


struct Private
{
   void foo(){};
}

class A:private Private
{
public:
   using Private::foo;
};

class B
{
   Private b;
public:
   void foo() {b.foo();}
};

A a;
B b;

b.foo() directly calls B::foo(), which calls Private::foo() but
a.foo() directly calls Private::foo(). Your compiler probably
will optimize the excess call away but private inheritance guarantees
the direct call of Private::foo().

Further private inheritance gives instant documentation that A uses
foo of Private with no changes. and using statements are ussually
shorter and less error prone than forwarding functions. Take your
pick.

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