[C++-sig] Re: Allocating objects on the heap by default.

[David Abrahams]

Nicodemus <nicodemus at globalite.com.br> writes:

> David Abrahams wrote:
>
>>Pyste is about providing
>>an even terser syntax for accomplishing the same things, and
>>'std::auto_ptr<A>' is not only longer but it repeats information.
>>Also, how will that interface work when you have a class with virtual
>>functions that you want to be held by auto_ptr?
>>  
>
> I think we can provide functions for the most common smart pointers to
> be registered directly:
>
> hold_with_auto_ptr(A)   # or perhaps: auto_ptr_holder(A)?
> hold_with_smart_ptr(A)
>
> And a more general purpose function for any other smart pointer:
>
> hold(A, 'my_smart_ptr<A>')
>
> It does duplicate information, but very little in my opinion.

I think having two such syntaxes is unneccessary; new smart pointer
varieties are sufficiently rare that the 2nd syntax isn't justified,
and they're *used* sufficiently often that writing:

  def my_smart_ptr(name):
      return 'my_smart_ptr<%s>' % name

is justified by the rest of the code that gets written... And
furthermore, as I keep asking:

  ** What about classes with virtual functions?? **

Do you want to force the user to be knowledgeable about the name of
the Pyste-generated callback class (they would have to write
'my_smart_ptr<A_callback>' or whatever it is)?  Do you want to ask
them to change their Pyste wrapping code just because they add a
virtual function to their C++ code?

-- 
Dave Abrahams
Boost Consulting
www.boost-consulting.com