I reported some important distinction between Dictionaries and Sets at
http://bugs.squeak.org/view.php?id=7258.
The problem has been introduced by the change of Association>>#=.
Logically, Dictionary should have been detached from Set at this time,
since it was no more a Set of associations as it used to.
Stéphane Ducasse <stephane.duca...@...> writes:
>
> This is interesting that you present that as a Bag. I'm too sick now
> (my brain
> is wandering across my room) to really reply something clever.
>
> I thought that a bag was more an counting elements container
>
For me the sole specification is that a Bag unlike a Set can hold
several equal elements.
The fact that it can count them fast rather than enumerating the whole
collection is an implementation detail (an important detail of course).
> > a) multiple values can be in the dictionary:
> > (Dictionary new) at: 'one' put: 1; at: 'first' put: 1; yourself.
>
> For me to be bag would mean more
>
> > dc := (DictionaryBag new) at: 'one' put: 1; at: 'one' put: 2;
> > yourself.
> dc at: one
> -> #(1 2)
>
> Stef
>
a DictionaryOfBags ?
One thing Dictionary is not : a Bag of associations.
Think of it as a Bag of values.
As long as you don't override a key, a Dictionary behaves like a Bag:
digits := 0 to: 9.
b := Bag new.
d := Dictionary new.
digits do: [:i | b add: i//2].
digits do: [:i | d at: i printString put: i//2].
digits do: [:i |
self assert: (b occurrencesOf: i) = (d occurrencesOf: i)].
Personnally, I would expect
d values.
to answer a Bag (unordered) rather than an Array (arbitrary order)...
The only advantage of an Array is that it is faster than a Bag...
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