Hi Christoph, I presume that Jakob is just suggesting using (at: key put: value) rather than (add: key -> value).

Le dim. 17 nov. 2019 à 17:36, Thiede, Christoph < Christoph.Thiede@student.hpi.uni-potsdam.de> a écrit :

Thank you for the review! This was actually intended, or what would expect the following to do?

Dictionary fromKeys: 'wasda' values: '84265'

*Von:* Squeak-dev squeak-dev-bounces@lists.squeakfoundation.org im Auftrag von Jakob Reschke forums.jakob@resfarm.de *Gesendet:* Sonntag, 17. November 2019 17:24:25 *An:* squeak-dev@lists.squeakfoundation.org *Betreff:* Re: [squeak-dev] The Inbox: Collections-ct.860.mcz

Is there a strong indication to use add: anAssociation over at:put: here? The latter is more idiomatic and does not use the implementation detail that a dictionary is made up of associations.

commits@source.squeak.org schrieb am Fr., 15. Nov. 2019, 13:59:

...

A new version of Collections was added to project The Inbox: http://source.squeak.org/inbox/Collections-ct.860.mcz

==================== Summary ====================

Name: Collections-ct.860 Author: ct Time: 15 November 2019, 1:58:56.418005 pm UUID: f6364e7f-08c8-694a-9060-21bc0a0c28d4 Ancestors: Collections-pre.857

Add convenience constructor for Dictionary

Dictionary fromKeys: 'wasd' values: '8426'

=============== Diff against Collections-pre.857 ===============

Item was added:

• ----- Method: Dictionary class>>fromKeys:values: (in category 'instance

creation') -----

• fromKeys: keys values: values

•   | dictionary |
  

•   self assert: [keys size = values size].
  

•   dictionary := self new: keys size.
  

•   keys with: values do: [:key :value |
  

•           dictionary add: key -> value].
  

•   ^ dictionary!
  
  
  
  

On Sun, 17 Nov 2019, Thiede, Christoph wrote:

Okay, I was thinking that #add: would raise an error if the key is already present. But it doesn't and replace the value.

In my opionion, Dictionary >> #add: is a remnant of the old days when bindings (class, global and pool) were always assotiations. It's goal was to let multiple dictionaries share the same binding. But, with the introduction of Binding & subclasses, this turned out to be a harder problem, as their classes need to be changed accordingly. That's something that isn't always done properly. E.g. if you have a Global in Undeclared, and declare it as a class variable, the binding's class will stay Global, however if you declare a class variable not in Undeclared, its binding will be an Association. Also, from wherever that Global was held a reference to, the reference is still there exposing the class variable.

Using #add: in #fromKeys:values: causes problems with dictionaries having their own #associationClass returning anything other than Association.

(Which I find a bit confusing because if the key is already present, it deletes the old value silently.)

The only method that raises an error if a key is already present seems to be Dictionary>>#newFrom:.

Maybe this commit should be edited (diff-diff):

• ----- Method: Dictionary class>>fromKeys:values: (in category 'instance creation') -----
• fromKeys: keys values: values

+       | dictionary | +       self assert: [keys size = values size]. +       dictionary := self new: keys size. +       keys with: values do: [:key :value |

- +               dictionary add: key -> value].

+ +               dictionary

• +  at: key

+ +  ifPresent: [:existing | self error: ('Duplicate key "{1}"' format: {key})] + +  ifAbsentPut: value].

You can't avoid the block around value, the argument of ifAbsentPut:. If you did so, and value were a block, it would be evaluated, and the value returned by that block would be stored in the dictionary instead of value itself.

Levente

+       ^ dictionary!

---

Von: Squeak-dev squeak-dev-bounces@lists.squeakfoundation.org im Auftrag von Nicolas Cellier nicolas.cellier.aka.nice@gmail.com Gesendet: Sonntag, 17. November 2019 18:37:07 An: The general-purpose Squeak developers list Betreff: Re: [squeak-dev] The Inbox: Collections-ct.860.mcz   Hi Christoph, I presume that Jakob is just suggesting using (at: key put: value) rather than (add: key -> value).

Le dim. 17 nov. 2019 à 17:36, Thiede, Christoph Christoph.Thiede@student.hpi.uni-potsdam.de a écrit :

  Thank you for the review! This was actually intended, or what would expect the following to do?


  Dictionary fromKeys: 'wasda' values: '84265'

---

Von: Squeak-dev squeak-dev-bounces@lists.squeakfoundation.org im Auftrag von Jakob Reschke forums.jakob@resfarm.de Gesendet: Sonntag, 17. November 2019 17:24:25 An: squeak-dev@lists.squeakfoundation.org Betreff: Re: [squeak-dev] The Inbox: Collections-ct.860.mcz   Is there a strong indication to use add: anAssociation over at:put: here? The latter is more idiomatic and does not use the implementation detail that a dictionary is made up of associations.

commits@source.squeak.org schrieb am Fr., 15. Nov. 2019, 13:59: A new version of Collections was added to project The Inbox: http://source.squeak.org/inbox/Collections-ct.860.mcz

  ==================== Summary ====================

  Name: Collections-ct.860
  Author: ct
  Time: 15 November 2019, 1:58:56.418005 pm
  UUID: f6364e7f-08c8-694a-9060-21bc0a0c28d4
  Ancestors: Collections-pre.857

  Add convenience constructor for Dictionary

  Dictionary fromKeys: 'wasd' values: '8426'

  =============== Diff against Collections-pre.857 ===============

  Item was added:
  + ----- Method: Dictionary class>>fromKeys:values: (in category 'instance creation') -----
  + fromKeys: keys values: values
  +
  +       | dictionary |
  +       self assert: [keys size = values size].
  +       dictionary := self new: keys size.
  +       keys with: values do: [:key :value |
  +               dictionary add: key -> value].
  +       ^ dictionary!

Hi Levente,

Friendly ping. :-) May I merge Collections-ct.921 into the Trunk? :-)

Best, Christoph

--- Sent from Squeak Inbox Talk

On 2020-11-16T10:43:34-06:00, christoph.thiede@student.hpi.uni-potsdam.de wrote:

See Collections-ct.921 :-)

Best, Christoph

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