I am gradually making progress with my binary floating-point software, but have had to rewrite several times as I have forgotten most of the details of how to do it! After 30 years, I can't say I am surprised. But I need to clean up workspace when a class (not object) is deallocated. I can't easily use attributes, as people suggested, because there is no anonymous storage built-in type. I could subvert one of the existing storage types (buffer, string etc.), but that is unclean. And I could write one, but that is excessive. So far, I have been unable to track down how to get something called when a class is destroyed. The obvious attempts all didn't work, in a variety of ways. Surely there must be a method? This could be in either Python or C. Thanks. Regards, Nick Maclaren, University of Cambridge Computing Service, New Museums Site, Pembroke Street, Cambridge CB2 3QH, England. Email: nmm1@cam.ac.uk Tel.: +44 1223 334761 Fax: +44 1223 334679
At 09:00 AM 2/28/2007 +0000, Nick Maclaren wrote:
I am gradually making progress with my binary floating-point software, but have had to rewrite several times as I have forgotten most of the details of how to do it! After 30 years, I can't say I am surprised.
But I need to clean up workspace when a class (not object) is deallocated. I can't easily use attributes, as people suggested, because there is no anonymous storage built-in type. I could subvert one of the existing storage types (buffer, string etc.), but that is unclean. And I could write one, but that is excessive.
So far, I have been unable to track down how to get something called when a class is destroyed. The obvious attempts all didn't work, in a variety of ways. Surely there must be a method? This could be in either Python or C.
Have you tried a PyCObject? This is pretty much what they're for: http://www.python.org/doc/1.5.2/api/cObjects.html And yes, they're still around today: http://www.python.org/doc/2.5/api/cObjects.html (with an extra PyCObject_SetVoidPtr API added in in 2.4).
On 2/28/07, Nick Maclaren <nmm1@cus.cam.ac.uk> wrote:
I am gradually making progress with my binary floating-point software, but have had to rewrite several times as I have forgotten most of the details of how to do it! After 30 years, I can't say I am surprised.
But I need to clean up workspace when a class (not object) is deallocated. I can't easily use attributes, as people suggested, because there is no anonymous storage built-in type. I could subvert one of the existing storage types (buffer, string etc.), but that is unclean. And I could write one, but that is excessive.
Can you explain the reason for cleaning up in this scenario? Are you rapidly creating and destroying temporary class objects? Why can't you rely on the regular garbage collection process? Or does you class create an external resource like a temp file? -- --Guido van Rossum (home page: http://www.python.org/~guido/)
participants (3)
-
Guido van Rossum -
Nick Maclaren -
Phillip J. Eby