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miss-used become: ???

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Nicolas Cellier

miss-used become: ???

UnscriptedPlayer>>assureUniClass
"Create a uniclass and become the receiver into it"

| anInstance |
anInstance := self rootClassForUniclasses instanceOfUniqueClass.
anInstance initializeCostumesFrom: self.
self become: anInstance.
^ anInstance

As I understand it, after the become: self is anInstance and anInstance is self.
So this would answer the original UnscriptedPlayer before the become...
Is this really the intention?
Otherwise, becomeForward: would work better.

Nicolas

Chris Muller-3

Re: miss-used become: ???

Does become: swap the references in the currently executing MethodContext too?

On Fri, Jun 8, 2012 at 4:34 PM, Nicolas Cellier
<[hidden email]> wrote:

> UnscriptedPlayer>>assureUniClass
> "Create a uniclass and become the receiver into it"
>
> | anInstance |
> anInstance := self rootClassForUniclasses instanceOfUniqueClass.
> anInstance initializeCostumesFrom: self.
> self become: anInstance.
> ^ anInstance
>
> As I understand it, after the become: self is anInstance and anInstance is self.
> So this would answer the original UnscriptedPlayer before the become...
> Is this really the intention?
> Otherwise, becomeForward: would work better.
>
> Nicolas
>

Nicolas Cellier

Re: miss-used become: ???

Try this

String>>becomeB
self become: 'b'.
^self first

^'a' becomeB

Nicolas

2012/6/9 Chris Muller <[hidden email]>:

> Does become: swap the references in the currently executing MethodContext too?
>
>
> On Fri, Jun 8, 2012 at 4:34 PM, Nicolas Cellier
> <[hidden email]> wrote:
>> UnscriptedPlayer>>assureUniClass
>> "Create a uniclass and become the receiver into it"
>>
>> | anInstance |
>> anInstance := self rootClassForUniclasses instanceOfUniqueClass.
>> anInstance initializeCostumesFrom: self.
>> self become: anInstance.
>> ^ anInstance
>>
>> As I understand it, after the become: self is anInstance and anInstance is self.
>> So this would answer the original UnscriptedPlayer before the become...
>> Is this really the intention?
>> Otherwise, becomeForward: would work better.
>>
>> Nicolas
>>
>

Chris Muller-3

Re: miss-used become: ???

So the whole method would seem to be useless then..

On Sat, Jun 9, 2012 at 10:17 AM, Nicolas Cellier
<[hidden email]> wrote:

> Try this
>
> String>>becomeB
> self become: 'b'.
> ^self first
>
> ^'a' becomeB
>
> Nicolas
>
> 2012/6/9 Chris Muller <[hidden email]>:
>> Does become: swap the references in the currently executing MethodContext too?
>>
>>
>> On Fri, Jun 8, 2012 at 4:34 PM, Nicolas Cellier
>> <[hidden email]> wrote:
>>> UnscriptedPlayer>>assureUniClass
>>> "Create a uniclass and become the receiver into it"
>>>
>>> | anInstance |
>>> anInstance := self rootClassForUniclasses instanceOfUniqueClass.
>>> anInstance initializeCostumesFrom: self.
>>> self become: anInstance.
>>> ^ anInstance
>>>
>>> As I understand it, after the become: self is anInstance and anInstance is self.
>>> So this would answer the original UnscriptedPlayer before the become...
>>> Is this really the intention?
>>> Otherwise, becomeForward: would work better.
>>>
>>> Nicolas
>>>
>>
>

Andreas.Raab

Re: miss-used become: ???

Chris Muller-3 wrote

So the whole method would seem to be useless then..

To the contrary. First of all, the obvious use here is along the lines of:

foo := Unscripted Player new.
foo assureUniClass.

This makes good sense as it converts foo from an UnscriptedPlayer
into a PlayerXYZ (usually attached to some morph). Returning the
'original' foo is a good idea too if one considers that assureUniclass
is an inplace modification and if the client of that code would need
a reference to the original the *only* way to obtain it is via returning
it from the method. I don't know if the original reference is ever used,
but it makes sense to give the client some way to keep a reference
to the original in case that is needed for some other purpose (undo
perhaps?).

Cheers,
- Andreas

Bert Freudenberg

Re: miss-used become: ???

In reply to this post by Chris Muller-3

On 2012-06-09, at 17:33, Chris Muller wrote:

> So the whole method would seem to be useless then..

No. It changes the player from an unscripted one into one that can have scripts.

The return value of assureUniClass is not used in the system, so it doesn't really matter.

However, I agree with Nicolas that becomeForward: would be more appropriate. In particular since the code reads like returning the new instance was the intention.

- Bert -

> On Sat, Jun 9, 2012 at 10:17 AM, Nicolas Cellier
> <[hidden email]> wrote:
>> Try this
>>
>> String>>becomeB
>> self become: 'b'.
>> ^self first
>>
>> ^'a' becomeB
>>
>> Nicolas
>>
>> 2012/6/9 Chris Muller <[hidden email]>:
>>> Does become: swap the references in the currently executing MethodContext too?
>>>
>>>
>>> On Fri, Jun 8, 2012 at 4:34 PM, Nicolas Cellier
>>> <[hidden email]> wrote:
>>>> UnscriptedPlayer>>assureUniClass
>>>> "Create a uniclass and become the receiver into it"
>>>>
>>>> | anInstance |
>>>> anInstance := self rootClassForUniclasses instanceOfUniqueClass.
>>>> anInstance initializeCostumesFrom: self.
>>>> self become: anInstance.
>>>> ^ anInstance
>>>>
>>>> As I understand it, after the become: self is anInstance and anInstance is self.
>>>> So this would answer the original UnscriptedPlayer before the become...
>>>> Is this really the intention?
>>>> Otherwise, becomeForward: would work better.
>>>>
>>>> Nicolas
>>>>
>>>
>>
>

Bert Freudenberg

Re: miss-used become: ???

On 2012-06-09, at 17:53, Bert Freudenberg wrote:

> However, I agree with Nicolas that becomeForward: would be more appropriate. In particular since the code reads like returning the new instance was the intention.

OTOH, Andreas has a point too ;)

- Bert -