confused by PRWidget initialisation

Hi, I'm writing this as PRWidget initialisation had me confused for a while, and I guess it might confuse other newcomers. I'd also like to check with the list that my understanding is correct. For example given the code below: PRDistribution>>childrenWidget ^ childrenWidget ifNil: [childrenWidget := (PRComponent named: 'children') componentClass: PRChildrenWidget; write: 2 using: PRChildrenWidget descriptionLevel; write: true using: PRChildrenWidget descriptionExpand; yourself ] and: PRChildrenWidget class>>descriptionExpand ^ MABooleanDescription new default: self defaultExpand; parameterName: 'expand'; accessor: #expand; label: 'Expand'; priority: 310; yourself I would have expected an accessor "PRChildWidget>>expand:" to be called with the value: 'true'. I created my PRWidget derived class based on this assumption. However my equivalent setter was not being called and a closer look showed PRChildWidget to have no setters only getters. The getter reads as: PRChildWidget>>expand ^ self read: #descriptionExpand What's actually happening is "PRComponent>>description" is being called, not as I'd imagined: "PRChildWidget>>description". tracing through the following code: PRComponent>>write: anObject using: aDescription (self basicDescription includes: aDescription) ifTrue: [ super write: anObject using: aDescription ] ifFalse: [ (anObject notNil and: [ aDescription isDocumentDescription ]) ifTrue: [ anObject owner: self ]. self settings at: aDescription put: anObject ] reveals the code: "self settings at: aDescription put: anObject" is called, so "true" is placed in a settings Dictionary keyed by: #descriptionExpand I've just about understood the code so far, and though I haven't traced through PRChildrenWidget instantiation it looks like in WAComponent>>initializeOwner:link: that the settings are copied to the newly created PRChildrenWidget object. Phew. I think I can see why there's complexity, but seems a shame that it in WAComponent>>initializeOwner:link: the code couldn't call the accessors of the componentClass assuming that the Magritte descriptions were configured to use an accessor pattern. Or perhaps I've misunderstood?? Cheers Nick