Basically I have an existing (maybe a rather large and complicated (existing) instance) that I want to add new member to.
Cheers N Hacks/attempts follow: from math import sqrt ############ try2 ############ duck_obj = [ i*i for i in range(25) ] # OR a large sparse matrix # I "want" to an a useful property, eg length, and retain the ducks existing properties. # I COULD try... setattr(duck_obj,"length",lambda: sqrt(sum(*duck_obj))) print duck_obj.length() # returns 70 duck_obj[0]=70+71 print duck_obj.length() # returns 71 ############ try2 ############ # **BUT** I'd rather encapsulate a the original instance somehow. # I presume that I could define a class to do this somehow? duck_obj = [ i*i for i in range(25) ] # OR a LargeSparseMatrix() dec = Vec(duck_obj) ??? print dec.length() # returns 70 duck_obj[0]=70+71 # original "large and complicated duck instance" print dec.length() # returns 71 Any hints on how I need to define Vec so that any kind of duck_obj can be decorated/wrapped/encapsulated. -- http://mail.python.org/mailman/listinfo/python-list
