On 09 Feb 2015, at 18:24, Nicolai Hess <nicolaihess@web.de> wrote:

I thought, Behaviors define the "behavior" of objects, therefore:

Integer is a behavior, because it defines the behavior of "integer objects"

Integer class is a behavior because it defines the behavior of the object "Integer".

5 isBehavior -> false.

Integer isBehavior -> true.

Integer class isBehavior -> true.

What about Traits?

Traits are "behavioral(?)", but they don't define the behavior alone, only the composition of

Traits in an actual class defines the behavior of an Object.

TClass isBehavior -> false.

So far so good.

In fact the first time I saw this I was a bit surprised, I was expecting it to return true.

After all Trait class inherits TraitBehavior that uses the TBehavior trait.��

Sure a trait alone doesn���t define the whole behavior of an object but at least part of it.

In fact it���s because there is many senders of isBehavior which expect it to return true only if the receiver is instanciable.

But still it���s a bit confusing.

Smalltalk globals allBehaviors includes:TClass -> true !

No suprise, because #allBehaviors explicitly collect all classes and traits.

But the question is, what do we want to call a "Behavior���?

I would prefer isBehavior to return true for traits and rename the current isBehavior to isInstanciable for exemple.

But this is quite a refactoring and it���s likely to break many things that are not in the image by default.

Likewise in SystemDictionary and SystemNavigation:

All Classes and MetaClasses (-> Behavior allSubclasses)

-> allInstanciable or allClassesAndMetaclasses

All Classes and Traits

-> allInstanceSideBehaviors (and an equivalent allClassSideBehavior for metaclasses and classtraits)

All Classes and Traits and MetaClasses and ClassTraits

-> allBehaviors

All Classes and MetaClasses and some Traits?

not this one

(this of course, is related to http://forum.world.st/RBEnvironments-allClasses-Traits-Meta-tp4796370.html).

In squeak Traits are behavior too.

Yes, it���s because in squeak traits are implemented differently: the class Trait inherits from Behavior so traits are instanciable.

nicolai