On Wednesday 28 March 2007 12:42:52 Bryce Hendrix wrote:
Thanks Pierre, works like a charm. One question though, how is defining a class attribute in __new__ any more thread-safe?
It's not, of course, and that's why it shouldn't be used. However, it's quite convenient and easier to use, and do you really need thread-safe objects ? In your example, if "yourdefaultunit" takes some simple value, you could use that value directly instead of the class attributes, which could be slightly messier to read but definitely thread-safe.
The second aspect about initialization is that when a ndarray is viewed as one of its subclasses, the actual memory space has already been allocated, so there's no call to __new__. Instead, you have to rely on __array_finalize__ to initialize the attributes specific to your subclass.