"Christoph J. Bachinger" <
[hidden email]> wrote in message
news:bo8das$1a270u$
[hidden email]...
> Adding a Dictionary contents to another Dictionary via
> addAll: causes an error due to the lack of an addAll:
> in Dictionary.
>
> An Example could be this
>
> addAll: newElements
> newElements associationsDo: [:each | self add: each].
> ^newElements
>
>
> or maybe better to be compatible with the older behavior
>
> addAll: newElements
> newElements isDictionary "Dolphin knows no isDictionary"
> ifTrue: [ newElements associationsDo: [ :assoc | self add:
assoc] ]
> ifFalse: [ newElements do: [ :each | self add: each ] ].
> ^newElements
>
> or do I understand anything wrong.
Christoph,
I'm not entirely sure I understand your issue completely, but perhaps these
observations are useful to you:
A <dictionary>, when seen as a <collection>, is conventionally considered to
be the collection of its values (i.e., not of its associations - they are an
implementation detail: many dictionaries are not implemented using
associations at all).
Using a <dictionary> as the receiver or as the argument of #addAll: is such
a case (of seeing a <dictionary> as a <collection>).
The other relevant convention for adding things to dictionaries is that if
you add them using #add: (as opposed to #at:put:) is that the things respond
to #key, so that #add: can be implemented as:
Dictionary>>add: anObject
self at: anObject key put: anObject
To make things even more complex, several Smalltalk dialects implement
#value in Object to return self, so that they can allow associations to be
added to a Dictionary by implementing:
Dictionary>>add: anObject
self at: anObject key put: anObject value
Finally, there is the general observation that #addAll: modifies the
receiver <collection> in the same way as multiple #add:'s in a #do: loop
over the argument <collection>.
Hope this helps instead of adding to the confusion ;-).
Cheers,
Peter van Rooijen
Amsterdam
Locked
