On Wed, Jul 27, 2016 at 8:13 AM, Joseph Alotta <joseph.alo...@gmail.com> wrote:
> Ben, Ron, I made a small example, and it works as you said it would:
>
> a := #( #(1 2) #(3 4)).
> b := a asOrderedCollection.
> b => an OrderedCollection(#(1 2) #(3 4))
> c := b select: [ :i | (i first) = 3 ].
Ahh. Code examples help. Maybe what you need is #detect:
which returns an element rather than a collection of elements.
> c => an OrderedCollection(#(3 4))
> d := c first
> d => #(3 4)
> d at: 2 put: 5
> d => #(3 5)
> b => an OrderedCollection(#(1 2) #(3 5))
>
> Okay, I will check my other code.
>
> Sincerely,
>
> Joe.
Here's a domain specific example...
Object subclass: #DrivingDays
instanceVariables: 'date store mileage"?" '
...etc...
oc := OrderedCollection new.
oc add: (DrivingDays new date: '2016-01-02' ; store: 'quigley' ; mileage: 18).
oc add: (DrivingDays new date: '2016-01-03' ; store: 'marianos' ; mileage: 5).
oc printString.
>> > an OrderedCollection(2016-01-02| quigley | 18,
>> > 2016-01-03| marianos | 5)
drivingDayToUpdate := oc detect: [ :dd | dd store = 'marianos' ].
drivingDayToUpdate mileage: 7.
oc printString.
>> > an OrderedCollection(2016-01-02| quigley | 18,
>> > 2016-01-03| marianos | 7)
(disclaimer, I am not somewhere I can run this. Its just off the top
of my head.)
cheers -ben
>
>
>
>
>> On Jul 26, 2016, at 6:25 PM, Ben Coman [via Smalltalk] <[hidden email]>
>> wrote:
>>
>> Hi Joe,
>>
>> As Ron said, you should not be getting a copy. If you still have a
>> problem, perhaps best if you post code for a complete example:
>> * class definition (with just two instance variables)
>> * instance variable accessor methods
>> * instance creation & adding to collection
>> * select statement
>> * updating object
>>
>> cheers -ben
>>
>> On Wed, Jul 27, 2016 at 5:53 AM, Ron Teitelbaum <[hidden email]> wrote:
>>
>> > Hi Joe,
>> >
>> > If the orderedCollection contains your object DrivingDays then select
>> > should give you the object and not a copy.
>> >
>> > You don't need to add it back to the collection just update the object.
>> >
>> > Check your code for anything that might be making a copy.
>> >
>> > All the best,
>> >
>> > Ron Teitelbaum
>> >
>> >
>> > -----Original Message-----
>> > From: [hidden email] [mailto:[hidden email]] On Behalf Of Joseph Alotta
>> > Sent: Tuesday, July 26, 2016 3:04 PM
>> > To: [hidden email]
>> > Subject: [Newbies] indexing into a collection
>> >
>> > Greetings,
>> >
>> > I have a OrderedCollection of DrivingDays.
>> >
>> >
>> > an OrderedCollection(2016-01-02| quigley s| nil|18§
>> > 2016-01-03| marianos fresh| nil|5§
>> > 2016-01-04| fresh thyme| nil|5§
>> > 2016-01-05| panda express| nil|3§
>> > 2016-01-06| peets| nil|7§
>> > 2016-01-07| starbucks| nil|3§)
>> >
>> > I want to select aDrivingDay object from the list by date, update it by
>> > adding mileage and places visited and put it back into the list.
>> >
>> > If I #select the OrderedCollection, I get a copy of the item, not the
>> > same one in the OrderedCollection.
>> >
>> > How do I select an item in the list for update?
>> >
>> > Sincerely,
>> >
>> > Joe.
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