Composing tree attributions

Using the simple tree attributions described in this paper, attribute values can themselves be trees, enabling attribution to be used for tree transformations. Unlike higher-order attribute grammars, simple tree attributions have the property of descriptional composition, which allows a complex transformation to be built up from simpler ones, yet be executed efficiently. In contrast to other formalisms that admit descriptional composition, notably composable attribute grammars, simple tree attributions have the expressive power to handle remote references and recursive syntactic (tree-generating) functions, providing significantly more general forms of attribution and transformation.