Improved struct module

[Greg Ewing]

Tim Peters wrote:
> 
> a buffer object contains a pointer to a base object and a
> separate pointer to a chunk of untyped memory.  If the base object happens
> to stop using that memory, there's no way for the buffer object to know
> that.

That sounds like a description of one way to mis-implement the
buffer interface of an object, rather than a flaw in the buffer
interface concept itself.

Are there any existing objects which have this problem? If so,
they should be fixed.

Greg