Re: [Boost-users] scoped_ptr::release (again)

Subject: Re: [Boost-users] scoped_ptr::release (again)
From: Nat Goodspeed (nat_at_[hidden])
Date: 2009-02-24 11:56:32

Christopher Jefferson wrote:

> I'd vote for keeping scoped_ptr as simple as possible, even removing 
> that swap, and directing people who want more power to unique_ptr.

I'd like to keep swap(). If the coder wants to disable it, wouldn't 
'const scoped_ptr' suffice?

If I have a class that supports assignment, and my class uses scoped_ptr 
to manage some resource, Herb Sutter's exception-safe assignment 
operator still applies:

1. Construct a new stack scoped_ptr with the incoming resource. An 
exception here leaves *this unmolested.
2. Swap the member scoped_ptr with the new scoped_ptr. (swap() is 
guaranteed not to throw.)
3. Leaving the assignment-operator method body destroys the temp stack 
scoped_ptr, releasing the member scoped_ptr's previous data.