The chart expressions are arranged hierarchically, with children inheriting properties from their parent. All chart expressions descend from a common parent, and get more specific as the hierarchy gets deeper. Understanding the hierarchy is key to understanding what properties are available on each chart type. Some properties are common across all chart types - these are at the highest level. Some properties are specific to categorical charts while others are specific to Pie-type charts. Here is the hierarchy:
So, looking at the above organization, BarChartExpression has properties from AbstractChartExpression, CategoricalChartExpression, and StackedCategoricalChartExpression, and it may have its own properties unique to Bar Charts as well. RingChartExpression has properties from AbstractChartExpression, and PieChartExpression. And, like the Bar Chart, may have additional properties that are unique to Ring Charts.
To avoid duplicating information, each of the expressions will be documented, and a reference to all of the ancestors will be included so it's possible to reference any additional properties.