Re: [Python-Dev] [numpy wishlist] Interpreter support for temporary elision in third-party classes

Nathaniel Smith wrote:

I'd be a little nervous about whether anyone has implemented, say, an iadd with side effects such that you can tell whether a copy was made, even if the object being copied is immediately destroyed.

I can think of at least one plausible scenario where this could occur: the operand is a view object that wraps another object, and its __iadd__ method updates that other object. In fact, now that I think about it, exactly this kind of thing happens in numpy when you slice an array! So the opt-in indicator would need to be dynamic, on a per-object basis, rather than a type flag. -- Greg