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Instance-specific behavior

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Sean P. DeNigris

Instance-specific behavior

Administrator

What would be the best way (as an experiment) to change the behavior of just one instance. For example, say:
SpecialMorph>>#color
^ Color blue.
but (the effect of)
aSpecialMorph>>#color
^ owner color.

Cheers,
Sean

Alejandro Infante

Re: Instance-specific behavior

Proxy maybe? I remember an example in Pharo by Example Book chapter 13 or 14.

So the main idea would be:

Create MyProxy, subclass of ProtoObject and with an instance variable.

MyProxy>>initialize

morph := self.

Override doesNotUnderstand to dispatch the message to the other object.

Also implement your custom behavior in the MyProxy.

Then use #become: to install the proxy. (The one that swaps all the references)

Cheers,

Alejandro

2014-02-04 Sean P. DeNigris <[hidden email]>:

What would be the best way (as an experiment) to change the behavior of just
one instance. For example, say:
SpecialMorph>>#color
^ Color blue.
but (the effect of)
aSpecialMorph>>#color
^ owner color.

-----
Cheers,
Sean
--
View this message in context: http://forum.world.st/Instance-specific-behavior-tp4741502.html
Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

pharo4Stef@free.fr

Re: Instance-specific behavior

In reply to this post by Sean P. DeNigris

Have a look at my old JOOP paper on message passing control
- you can have anonymous subclasses
where you compile some methods+ changeclass.

Stef
On 04 Feb 2014, at 19:30, Sean P. DeNigris <[hidden email]> wrote:

> What would be the best way (as an experiment) to change the behavior of just
> one instance. For example, say:
> SpecialMorph>>#color
> ^ Color blue.
> but (the effect of)
> aSpecialMorph>>#color
> ^ owner color.
>
>
>
> -----
> Cheers,
> Sean
> --
> View this message in context: http://forum.world.st/Instance-specific-behavior-tp4741502.html
> Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.
>

Sean P. DeNigris

Re: Instance-specific behavior

Administrator

Pharo4Stef wrote

Have a look at my old JOOP paper on message passing control

Found it - thanks :)

Cheers,
Sean