"itsme213" <itsme213 at hotmail.com> wrote
> Say I have a trait which manipulates a collection inst-var: ....

I had the #x->#y backwards in my last post. Below is the full example, 
cleaned up and better named:

Say I have a trait which manipulates a collection inst-var:

Trait named #TCollectionInstVar
  >> addToInstVar: x
            self iVar add: x
  >> removeFromInstVar: x
            self iVar remove: x
  >> doOverInstVar: aBlock
            self iVar do: aBlock

I have a class which could use this trait on two of its instance-variables:

Object subclass: Person
   instanceVariableNames: 'cars houses'
Person>>cars
   ^ cars ifNil: [cars := OrderedCollection new]
Person>>houses
   ^ houses ifNil: [houses := OrderedCollection new]

I want to use TCollectionInstVar on my Person class, twice, on #cars and
#houses. I need to rename both provided & required methods to do this:
  TCollectionInstVar @ {
    #addCar: -> #addToInstVar: .
    #removeCar: -> #removeFromInstVar: .
    #doCars: -> #doOverInstVar: }
   requiring: { #iVar -> #cars } "change 'self iVar' to 'self cars'"
and
  TCollectionInstVar @ {
    #addHouse: -> #addToInstVar:
    #removeHouse: -> #removeFromInstVar.
    #doHouses: -> #doOverInstVar: }
   requiring: { #iVar -> #houses } "change 'self iVar' to 'self houses'"

This would be equivalent to using two (anonymous, auto-generated) traits
which are derived from TCollectionInstVar, which rename the required method
from #iVar to #cars and #houses, respectively (i.e. any send of "self iVar"
is rewritten to a "self cars" or "self houses").

Since many behaviors of an object are focused on just some part of its state 
(wrapped by accessors), I find many places where I want to parameterize a 
trait by the "required method" it will use to "call-back" to my class. 
Having this "call-back" hard-coded in the trait with no way to override 
makes that trait much less re-usable.

As Andreas pointed out, this would be solved with proper "renaming" of 
methods (both provided and required, probably written #old->#new, not 
#new->#old) when using traits, as opposed to the current "aliasing".

Hope I was clearer that time, and please tell me if I should be thinking 
differently about this.

Thanks - Sophie