alternative implementation of PRCommand which takes a #prototypeInstance: so PRStructure>>defaultEnvironment now reads as:

addChild: ((PRComponent named: 'search')

prototypeInstance: PRSearchWidget new;

yourself);

addChild: ((PRComponent named: 'children')

prototypeInstance: (PRChildrenWidget new

level: 1;

yourself);

yourself);

addChild: ((PRPage named: 'sidebar')

addChild: ((PRComponent named: 'navigation')

prototypeInstance: (PRChildrenWidget new

level: 2;

expand: true

yourself);

yourself);

addChild: ((PRComponent named: 'views')

prototypeInstance: PRViewsWidget new;

yourself);

addChild: ((PRComponent named: 'commands')

prototypeInstance: PRCommandsWidget new;

yourself);

whereas my first attempt using #write:usingNamed looks like:

addChild: ((PRComponent named: 'search')

componentClass: PRSearchWidget;

yourself);

addChild: ((PRComponent named: 'children')

componentClass: PRChildrenWidget;

write: 1 usingNamed: #descriptionLevel;

yourself);

addChild: ((PRPage named: 'sidebar')

addChild: ((PRComponent named: 'navigation')

componentClass: PRChildrenWidget;

write: 2 usingNamed: #descriptionLevel;

write: true usingNamed: #descriptionExpand;

yourself);

addChild: ((PRComponent named: 'views')

componentClass: PRViewsWidget;

yourself);

addChild: ((PRComponent named: 'commands')

componentClass: PRCommandsWidget;

yourself);

The alternative implementation with prototypeInstances simplifies PRComponent, and is more efficient (though I doubt that is significant with the larger context of Pier). Another advantage is that there is less of a conceptual jump for people making a move from WAComponents to PRWidgets - as it allows an alternative form of widget development. That is widgets can use instance variables to hold their state rather than being required to map state onto #properties stored within PRWidget. As an example I've modified PRBatcherWidget, PRContentsWidget, PRHtmlWidget, PRSearchWidget and PRTocWidget to use this instance variable state holding form of widgets. Other widgets keep the old property mapping form, and to support both forms I've introduced a new base PRWidgetPropertyBase, which encapsulates the property support.

The prototypeInstance implementation does require that PRWidgets implement setters; in the examples above I had to modify PRChildenWidget to add #level: and #expand:. I've modified all PRWidgets to add setters - potentially this could be automated through a refactoriing or rewrite rule.