RFC: Proposal: Deterministic Object Destruction

ooomzay at gmail.com ooomzay at gmail.com
Fri Mar 2 08:55:42 EST 2018


On Friday, March 2, 2018 at 12:22:13 AM UTC, MRAB wrote:
> On 2018-03-01 23:38, ooomzay wrote:
[Snip]
> > PEP343 requires two new methods: __enter__ & __exit__.
> > RIAA requires no new methods.
> >
> > RIAA resources are invariant: If you have a reference to it you can use it.
> > PEP343 resources can not be invariant: To be robust the enter/exit state
> > must be tracked and checked. (assert self.handle in the example)
[Snip]
> > PEP343 requires specialised "with" syntax, RIAA requires no new syntax.
> > Furthermore, although src & dst objects are still accessible outside the
> > PEP343 "with" block they are not in a usable state (not invariant).
> > 
> > In the RIAA case the resources are guaranteed to be in a usable state as long
> > as any reference exists (invariant). References can also be safely
> > passed around.The resource will be freed/closed when the last man has finished
> > with it, even in the face of exceptions.
> > [snip]
> >
> What's the difference between 'RAIIFileAccess' and 'open'?

I listed all the differences I know of in my preceding post. (I have snipped the other stuff so they are easy to see).



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