* `expandValue()` --
TODO: either document this or remove it from the API.
-* TODO subwidget()
+* `subwidget(type, overrides, defaults)` --
+ Returns the HTML of a subwidget of the specified type, which
+ can then be inserted into the widget using the
+ `this.node.html` function. The subwidget is given the same
+ attributes at the parent widget that invokes this function,
+ except where overrides are passed in. If defaults are also
+ provided, then these are used when the parent widget provides
+ no values. Both the `overrides` and `defaults` arguments are
+ hashes: the latter is optional.
+
+ See for example the `Credo` widget defined in the example
+ area's `mkws-widget-credo.js` file. This uses several
+ invocations of `subwidget` to create a complex compound widget
+ with numerous text, facet and image panes. TODO: rename this
+ widget and everything related to it.
In addition to these properties and methods of the bare widget object,
some kinds of specific widget add other properties of their own. For