[sage-devel] Re: [sage-combinat-devel] Freezing

2010-05-17 Thread Jason Grout
On 5/15/10 4:46 PM, Bruce wrote: Could a determined user then add a method which did modify the data? By the open nature of python, a determined user could *always* add a method which modified the data. Many of the conventions in python are not enforced, and rely on the user behaving

[sage-devel] Re: [sage-combinat-devel] Freezing

2010-05-16 Thread Nicolas M. Thiery
Dear Bruce, dear graph fans, On Sat, May 15, 2010 at 02:46:14PM -0700, Bruce wrote: I am continuing a discussion in a new post. The issue is that if we take a class such as graphs the instances are mutable. It would be useful to have a version which was immutable and therefore