[Newbies] Re: Recap: How to empty a collection

[Klaus D. Witzel]

On Wed, 20 Feb 2008 23:05:47 +0100, nicolas cellier wrote:

> Klaus D. Witzel a écrit :
>> On Wed, 20 Feb 2008 02:01:49 +0100, nicolas cellier wrote:
>>
>>> Some proposed an alternative based on (self removeAll: self), and  
>>> started writing optimized versions of #removeAll:.
>>  No, (anOrderedCollection removeAll: anOrderedCollection) was not  
>> optimized. It had a *very* long known bug, which was fixed. Please do  
>> less mixing of subjects in threads.
>>
>
> OK, I'm extrapolating.

O.K. the fix from OrderedCollection *could* be applied to Set (the fix  
requires #copyEmpty), but see Heap below.

> In this case, while you are at it:
>
> 	| aSet |
> 	aSet :='Klaus' asSet.
> 	aSet removeAll: aSet.
> 	aSet
> 	
> 	| aHeap |
> 	aHeap := Heap withAll: 'Witzel'.
> 	aHeap removeAll: aHeap.
> 	aHeap

Don't use Heap much, it is not very conformant; example: (Heap withAll:  
'array') reject: [:x | x = $r] => an Array. Perhaps people didn't know  
about *all* senders of #species ...

>
> I would have used my name, but it seems i am removeable ;-)
> 	| aSet |
> 	aSet :='Cellier' asSet.
> 	aSet removeAll: aSet.
> 	aSet
>
> Try with the collection of your choice.
>
> In the mean time, don't use (self removeAll: self)...

One step after the other :) no doubt #removeAll: gets fixed, perhaps in  
the next release?

> Yes i'm mixing threads,should be How to NOT empty a collection ;-)
>
> Nicolas
>
>>> I think our biggest problem is that we have plenty possible ways to do  
>>> it... Finding a balance between genericity and efficiency...
>>  No, more correctness at the price of less efficiency :)
>>
>>> Nicolas
>
> Agree on this one.
> Then allow removeAllSuchThat: as default implementation.
>
> Nicolas