[Python-Dev] Pre-PEP: Allow Empty Subscript List Without Parentheses

Greg Ewing greg.ewing at canterbury.ac.nz
Sat Jun 10 02:02:30 CEST 2006

Tim Hochberg wrote:

> In Numpy, a 0-D array [for example, array(5)] is almost, but not quite, 
> equivalent to  scalar [for example, 5]. The difference is that the 
> former is mutable.

Hmmm, I hadn't considered that. I suppose this is
something that arises from NumPy's "view" semantics
of indexing and slicing.

> Whether that makes x[] desirable I won't venture an opinion. I don't see 
> a lot of use of 0-D arrays in practice.

Actually, I *have* just thought of a use for it:

   def outer():
     x = array(0)
     def inner():
       x[] = 42

Bingo - write access to outer scopes!

Okay, I'm +0 on this now. But for that use, we'd need
a more convenient way of creating one than importing
NumPy and using array().


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