Duncan Booth wrote: > Alex Martelli wrote: > >> It IS true that in Python you cannot set arbitrary attributes on >> arbitrary objects. The workaround is to use a dict, indexed by the id >> of the object you want to "set arbitrary attributes on"; this has the >> helpful consequence that separate namespaces are used, so your arbitrary >> setting of metadata cannot interfere with the `true' attributes of the >> object in question. >> > That's a horrible suggestion (using id's, not the bit about separate > namespaces). If you use the id then attributes will persist beyond the > lifetime of the object and may suddenly reappear on other unrelated objects > later. > > A better suggestion here would be to use weak references. Unfortunately, > not every Python object can be the target of a weak reference, so there is > a limitation here preventing a useful implementation for many builtin > types.
mxProxy could help with that: http://www.egenix.com/files/python/mxProxy.html It allows creating weak references to any Python object (among other things like protecting object access). -- Marc-Andre Lemburg eGenix.com Professional Python Services directly from the Source (#1, Jan 13 2006) >>> Python/Zope Consulting and Support ... http://www.egenix.com/ >>> mxODBC.Zope.Database.Adapter ... http://zope.egenix.com/ >>> mxODBC, mxDateTime, mxTextTools ... http://python.egenix.com/ ________________________________________________________________________ ::: Try mxODBC.Zope.DA for Windows,Linux,Solaris,FreeBSD for free ! :::: -- http://mail.python.org/mailman/listinfo/python-list
