[Python-Dev] syntactic support for sets

Fri Feb 3 17:09:34 CET 2006

On Fri, 2006年02月03日 at 12:04 +0000, Donovan Baarda wrote:
> On Wed, 2006年02月01日 at 13:55 -0500, Greg Wilson wrote:
[...]
> Personally I'd like this. currently the "set(...)" syntax makes sets
> feel tacked on compared to tuples, lists, dicts, and strings which have
> nice built in syntax support. Many people don't realise they are there
> because of this.
[...]
> Frozensets are to sets what tuples are to lists. It would be nice if
> there was another type of bracket that could be used for frozenset...
> something like ':1,2,3:'... yuk... I dunno.

One possible bracket option for frozenset would be "<1,2,3>" which I
initially rejected because of the possible syntactic clash with the <
and > operators... however, there may be a way this could work... dunno.
The other thing that keeps nagging me is set, frozenset, tuple, and list
all overlap in functionality to fairly significant degrees. Sometimes it
feels like just implementation or application differences... could a
list that is never modified be optimised under the hood as a tuple?
Could the immutability constraint of tuples be just acquired by a list
when it is used as a key? Could a set simply be a list with unique
values? etc.
-- 
Donovan Baarda <abo at minkirri.apana.org.au>
http://minkirri.apana.org.au/~abo/