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NNTP-Posting-Date: Thu, 12 Apr 2012 12:18:12 -0500
From: Gareth Owen <gwowen@gmail.com>
Newsgroups: comp.lang.c++
Subject: Re: Terminology - RAII vs. Scope Guard vs...?
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Juha Nieminen <nospam@thanks.invalid> writes:

>   The wikipedia page also seems to assume that RAII is just about scope-based
> construction and destruction of objects, as indicated for example by giving
> the gcc extension "cleanup" variable attribute as an example on how to
> emulate RAII in C. However, it's not just about construction and destruction
> of objects. One extremely important part of RAII is copying (both in the
> form of copy constructors and assignment operators).

I don't think that's an unreasonable distinction. Clearly, copying
semantics have to be well defined for any RAII-like
resource-management-through-ownership idiom/scheme/philosophy to work,
but you don't need C++ copy/assignment.

You could define 

* a language that forces copyable object to have a java-like
  user-provided clone() for all objects, and no implicit copying or
  assignment for user defined types (just as many C++ polymorphic
  classes do)
* or a language where every object acted like std::shared_ptr 
* or even (god forbid) a language where every object acted like
  std::auto_ptr

and still have RAII, just as long as you had destruction when the last
reference vanished.