On Tue, Nov 19, 2019 at 10:58 PM Chris Muller <asqueaker at gmail.com> wrote:

> They share the same selector API, but for ArrayedCollection's, it culls
> integers 1 to: n, while for non-Arrayed, it culls nil over and over.
>

Woops, I got that wrong, sorry.  It is the index in both cases, not nil.
That's better but, still, I'm sure I would just write collect:as: without
remembering this.

 - Chris



>   This means the sender will have to know whether it's Arrayed or not
> anyway (otherwise you'd need a nil check inside the loop).  And so, if you
> have to know that, one could just write classic Smalltalk.
>
>    (1 to: 20) collect: [ :i | ... ]
>
> (with or without an "as:" converter on the end).
>
> OTOH, if you were expecting a non-arrayed collection, then simply:
>
>     Array streamContents: [ : stream | ... ]
>
> I do appreciate the readability for people less experienced with
> Smalltalk, but for the long run, classic, readable, portable Smalltalk may
> actually be the better way for them to read it.
>
> Collecting nil over and over could be a sign of something not fully
> optimized here.
>
> -1 on this one, even though I'm really enjoying many of your other
> contributions, Christoph.
>
> Best,
>   Chris
>
> On Fri, Sep 6, 2019 at 9:57 AM <commits at source.squeak.org> wrote:
>
>> A new version of Collections was added to project The Inbox:
>> http://source.squeak.org/inbox/Collections-mt.852.mcz
>>
>> ==================== Summary ====================
>>
>> Name: Collections-mt.852
>> Author: mt
>> Time: 6 September 2019, 4:57:45.245608 pm
>> UUID: 3582be1c-a006-ed46-a517-3d2d570db6cc
>> Ancestors: Collections-mt.851
>>
>> Proposal: Initialize a new collection with a computation block without
>> needing an existing collection to #collect: from.
>>
>> OrderedCollection new: 20 filledWith: [100 atRandom].
>>
>> Thanks to Christoph (ct) for the idea.
>>
>> If we want this in Trunk, there will be tests. :-)
>>
>> =============== Diff against Collections-mt.851 ===============
>>
>> Item was added:
>> + ----- Method: ArrayedCollection class>>new:filledWith: (in category
>> 'instance creation') -----
>> + new: size filledWith: aBlock
>> +       "Similar to #collect:as: and #fillFrom:with: but uses only the
>> interval (1 to: size) to fill the collection. Different compared to
>> #new:withAll: because aBlock can return different values for each index."
>> +
>> +       | result |
>> +       result := self new: size.
>> +       1 to: size do: [:each | result at: each put: (aBlock cull: each)].
>> +       ^ result!
>>
>> Item was added:
>> + ----- Method: Collection class>>new:filledWith: (in category 'instance
>> creation') -----
>> + new: size filledWith: aBlock
>> +       "Similar to #collect:as: and #fillFrom:with: but uses only the
>> interval (1 to: size) to fill the collection. Different compared to
>> #new:withAll: because aBlock can return different values for each index."
>> +
>> +       | result |
>> +       result := self new: size.
>> +       1 to: size do: [:each | result add: (aBlock cull: each)].
>> +       ^ result!
>>
>>
>>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.squeakfoundation.org/pipermail/squeak-dev/attachments/20191120/54fd9563/attachment.html>