Hi,

The "set" is a mathematical object which is defined by what it contains, there isn't any order concept in it.

So, by definition of set: {1,2,3} = {2,3,1}

It makes not even sense to ask what is the first element of a set, because there is no order in it.

So, I guess Christoph is giving you the right hint, keep working with OrderedCollection.

Then, you may open your Squeak, on top of the Window select Help -> Terse Guide To Squeak
and check ouy "Bag" and "Set" sections.

bye
n.



On 2/11/20 7:11 AM, Thiede, Christoph wrote:

Hi tty,


Set does not guarantee the order of elements. It's an implementation detail. If you only need to remove duplicates, have a look at #withoutDuplicates.


Does this help? :-)

Best,
Christoph
Von: Beginners <beginners-bounces@lists.squeakfoundation.org> im Auftrag von tty <gettimothy@zoho.com>
Gesendet: Dienstag, 11. Februar 2020 16:07:15
An: beginners@lists.squeakfoundation.org
Betreff: [Newbies] Does Set respect ordering?
 
Hi Folks.


If I have an OrderedCollection and convert it to Set via asSet, am I
guaranteed that the resulting Set contains elements in the same order as the
OrderedCollection?

Here is my problem.

I have an OrderedCollection with the same element in it twice. By same
element, I mean they are the same object.

*an OrderedCollection(
A
NESTED  TABLE CELL
 
B
A
NESTED  TABLE CELL

)
*

Above, the first and third elements are the same XMLElement. I now this
because if I inspect them and then change one, the other changes.

if I run asSet on the OrderedCollection, I get what I need:

*a Set( A
NESTED  TABLE CELL
 
B)*


In that conversion, can I rely on that Ordering being preserved?

If not, a pointer to the correct select/reject/inject/detect...sort of thing
would be much appreciated.

cheers.







--
Sent from: http://forum.world.st/Squeak-Beginners-f107673.html
_______________________________________________
Beginners mailing list
Beginners@lists.squeakfoundation.org
http://lists.squeakfoundation.org/mailman/listinfo/beginners
 
_______________________________________________
Beginners mailing list
Beginners@lists.squeakfoundation.org
http://lists.squeakfoundation.org/mailman/listinfo/beginners