Hello Marcel,

#joinSeparatedBy: looks well, unfortunately it is only available for SequencableCollections. I would like some convenience method for other species of Collections as well:

#(1 2 3) asSet joinSeparatedBy: '-'

Could we rename my proposed method into #asStringByDelimiter: and add it to Collection?

Best, Christoph

-- Sent from: http://forum.world.st/Squeak-Dev-f45488.html

Hi Chris,

On Fri, May 31, 2019 at 04:53:41PM -0500, Chris Muller wrote:

Hi Christoph,

It would be preferable to move #joinSeparatedBy: to Collection than increase the existing API with a new, differently-named method that does the same thing.

Just in case you weren't aware -- if its the same implementation and you wish to preserve original author and timestamp information (recommended), you can use drag-and-drop to move the method! Open two windows side-by-side, one on Collection, the other on SequenceableCollection. Select joinSeparatedBy: and drag it to that category in Collection. Done. No new tests needed either, since they already exist.

Thanks for that tip. Sometimes I'm amazed by my own ignorance. For years, I have been in the habit of preserving timestamp information by filing something out, editing the fileout file with a unix vi editor to hack it to the new destination class/category, and then filing it back in.

Boy am I dumb :-)

Thanks, Dave

On 31/05/19 6:04 PM, Christoph Thiede wrote:

#(1 2 3) asSet joinSeparatedBy: '-

What is the expected answer for joining set members by '-'?

If I have a set with members #daa, #dee, #dum, the output could be any of 'daa-dee-dum', 'daa-dum-dee', 'dum-dee-daa', ....

Squeak 5.2alpha shows the order as 'dee-daa-dum'

Regards .. Subbu

...

On 31/05/19 6:04 PM, Christoph Thiede wrote:

...

#(1 2 3) asSet joinSeparatedBy: '-

What is the expected answer for joining set members by '-'?

If I have a set with members #daa, #dee, #dum, the output could be any of 'daa-dee-dum', 'daa-dum-dee', 'dum-dee-daa', ....

Squeak 5.2alpha shows the order as 'dee-daa-dum'

I think that's why #joinSeparatedBy: was initially only on sequenceable collection.

It can be good to start out behaviors in the most-restrictive place possible, because it's easier to relax something later if necessary, than to tighten it.

I mean, it is also unclear what joinSeparatedBy: would mean on a Bag with multiple occurrences, or a Matrix, or a Bitset…

The method only uses #do:, which is required of all Collections, so it's not any less clear than #do: on those objects.

On the other hand, you can always do things like myCollection asArray joinSeparatedBy: 'fnord' or myBag cumulativeCounts joinSeparatedBy: ', ' or (mySet sorted: [:a :b | a >= b]) joinSeparatedBy: ' is more than '

and be explicit on what you expect to establish the sequence.

It sounds like Christoph has a use case to join objects without caring about the order. I don't find that surprising, the method is a very abstract behavior, with many different uses across different domains. The existing implementation works in the context of any Collection, and those things you mentioned above can all still be done.

Regards, Chris

I agree with Tobias and Subbu, random order makes the feature questionable. Please try to write a TestCase to illustrate the expectations in case of non sequenceable collections.

Le dim. 2 juin 2019 à 07:58, K K Subbu kksubbu.ml@gmail.com a écrit :

On 02/06/19 12:25 AM, Chris Muller wrote:

...

The method only uses #do:, which is required of all Collections, so it's not any less clear than #do: on those objects.

Chris,

#do: does yield a sequence but the order is not guaranteed to be same from one send to another.

The provided test case for #joinSeparatedBy: assumed a particular sequence. When Christoph proposed to relax it for all Collections, the existing test cases will also have to change to avoid false fails.

Regards .. Subbu

My use case was about concatenating strings in order to build a filter string (where order does not matter), but I agree this can be achieved using asArray as well.

My desire was to make #asCommaString and #joinByDelimiter: consistent, so why not move asCommaStringWithAnd etc. down to OrderedCollection and rename it to joinWithComma etc.?

Best, Christoph

-- Sent from: http://forum.world.st/Squeak-Dev-f45488.html

My use case was about concatenating strings in order to build a filter string (where order does not matter), but I agree this can be achieved using asArray as well.

Sending #asArray would introduce the unnecessary creation of an interim collection for every single query, even while making the code unnecessarily wordy and harder to read.

My desire was to make #asCommaString and #joinByDelimiter: consistent, so why not move asCommaStringWithAnd etc. down to OrderedCollection and rename it to joinWithComma etc.?

Goran had a mini-family of methods that does this same thing in Collection since 2005. Adding all of the above up, it seems very clear that the 2015 addition of #joinSeparatedBy: must not have noticed all of the above, so was inserted into a different place while duplicating the existing implementation.

Your use case disproved the theory that "it doesn't make sense". It makes perfect sense. We should just move it to Collection, and remove asCommaString and change senders to use this method.

- Chris

...

Sending #asArray would introduce the unnecessary creation of an interim collection for every single query, even while making the code unnecessarily wordy and harder to read.

You assume that it would be a common case to join non-seq collections. I argue that this is not the case. In those situations where you do have a non-seq collection, it would help readability to make the order explicit.

+1

Stef

On Mon, Jun 03, 2019 at 10:52:47AM +0200, St??phane Rollandin wrote:

...

I agree with Tobias and Subbu, random order makes the feature questionable.

+1

Stef

+1

I agree with Tobias and Subbu and Stef. Random order makes the feature questionable.

I also find the "aSet asArray" idiom to be quite comfortable. In a unix shell I often find myself doing "cat aFile | sort | uniq" and I rather prefer the Smalltalk idiom of "aCollection asSet asArray".

Dave