Re: [boost] Pimpl Again?

1 Jun 2016

      On May 31, 2016 7:13:53 PM EDT, Emil Dotchevski  wrote:
...
On Tue, May 31, 2016 at 4:07 PM, rstewart  wrote:
...
"Emil Dotchevski"  wrote:
...
On Tue, May 31, 2016 at 2:45 PM, Rob Stewart 
wrote:
...
On May 31, 2016 5:10:35 PM EDT, Emil Dotchevski <
emildotchevski@gmail.com>
wrote:
...
header:
struct foo { int critical_; };
shared_ptr<foo> create_foo();
inline void use_foo_critical( foo * p ) { ++p->critical_; }
void use_foo_not_so_critical( foo * )
Were you leaving encapsulation as an exercise for the reader?
class foo
{
public:
   use_critical () { ++critical_; }
protected:
   int critical_;
};
Your foo_ can still access critical_.
Right, though my preference is as follows.
//Public interface:
namespace boost { template <class> class shared_ptr; }
You can't do the same thing with std::shared_ptr. Besides, the user of your foo will need the definition of the same shared_ptr as does create_foo(), do you save anything by avoiding the include directive?
...
...
...
class foo;
boost::shared_ptr<foo> create_foo();
void use_foo_critical( foo * );
void use_foo_not_so_critical( foo * );
//Implementation details:
class foo
{
  foo( foo const & );
  foo & operator=( foo const & );
  int critical_;
  friend void use_foo_critical( foo * );
protected:
  foo();
  ~foo();
};
inline void use_foo_critical( foo * p ) { ++p->critical_; }
That doesn't provide inline access to those with access only to the
header.
I meant that whole thing being in the header, which is required for
inline
access (within the CPP file inline is next to pointless since the
compiler
can easily inline any function.) The point I'm making with
"//implementation details" is that the fact that use_foo_critical is
defined inline, as well as the exact definition of foo itself, is not
part
of the interface and thus subject to change.
As you guessed, I assumed that "Implementation details" referred to code in a separate source file.

Unlike a detail namespace, a mere comment separates users from what you consider implementation details. The compiler can't help you, though I suppose you can implement, in the header, only what needs exposure for performance reasons.

___
Rob

(Sent from my portable computation engine)