On 6 Feb 2019, at 13:25, Vitor Medina Cruz <vitormcruz@gmail.com> wrote:

Thanks, I was looking for usages of InstanceVariableSlot.

All instance variables are InstanceVariableSlots. 

But to make it less verbose, we have a way to specify these without having to put the name. 


Object subclass: #Point
slots: { #x. #y }
classVariables: {  }
package: 'Kernel-BasicObjects���

is the same as

Object subclass: #Point
slots: { #x => InstanceVariableSlot . #y => InstanceVariableSlot}
classVariables: {  }
package: 'Kernel-BasicObjects'

If you evaluate:

Point slotNamed: #x 

you see that it returns a 

    #x => InstanceVariableSlot

Slot instance.

(with all that: I sometime wonder if we should not get rid of the name ���Slot��� and just use the term ���Variable������ because that is what they are���)



In the case of SlotExampleMovie, #name and #year are of IntanceVariableSlot layout (this definition is correct? A slot is or has some Layout defined by the Slot class?)

No, the class has a Layout. See subclasses of AbstractLayout. This reifies the magic number that is in the ���format��� ivar of Behaviors (third ivar of all class like objects).

In addition it makes class definition *explicitly* specify the layout.

So Array in ST 80 is something like:

ArrayedCollection variableSubclass: #Array
instanceVariableNames: ''
classVariableNames: ''
package: 'Collections-Sequenceable-Base'

so the layout chosen is hidden in the class creation method (variableSubclass���), while with the reified layouts, it explicit:

ArrayedCollection subclass: #Array
layout: VariableLayout
slots: {  }
classVariables: {  }
package: 'Collections-Sequenceable-Base��� 

e.g. for CompiledMethod it makes clear that is a very special class:

CompiledCode subclass: #CompiledMethod
layout: CompiledMethodLayout
slots: {  }
classVariables: {  }
package: 'Kernel-Methods���




On Wed, Feb 6, 2019 at 10:14 AM Marcus Denker <marcus.denker@inria.fr> wrote:


> On 6 Feb 2019, at 12:41, Denis Kudriashov <dionisiydk@gmail.com> wrote:
>
> Would be nice to have a command in browser to show users of selected slot
>

Yes!

        Marcus