On Sat, 24 Mar 2007 23:43:10 -0700, bullockbefriending bard wrote: > z_list = [Z(y.var1, y.var2,..) for y in list_of_objects_of_class_Y] > > Of course this just gives me a plain list and no access to the > methodsof z_list.
List comprehensions give you a list. If you want to convert that list into the type of z_list, you need to do it yourself. Since ZList sub-classes from list, probably the easiest way is just: z_list = ZList([some list comprehension here]) > I could, of course go and write a static method in > ZList which takes a plain list of Z objects and returns a ZList. Yes, that would be one such way. Another way is: z_list.extend([some list comprehension here]) If you are using a recent enough version of Python, you probably don't even need the list comprehension. Just use a generator expression: z_list.extend(Z(y.var1, y.var2,..) for y in list_of_objects_of_class_Y) That's especially useful if the list of objects is huge, because it avoids creating the list twice: once in the list comp, and once as z_list. -- Steven. -- http://mail.python.org/mailman/listinfo/python-list
