Deriving Event-based Document Transformers from Tree-based Speciications

The event-based document transformers, which process a structured document simply as a stream of parsing events, have an advantage over the conventional tree-based ones that they can avoid the unnecessary intermediate data construction. This paper proposes an algorithm which derives an event-based transformer from a given speci-cation of a document transformation. The derivation of an event-based transformer is carried out in the framework of attribute grammars. We rst obtain an attribute grammar for the event-based transformer by applying a deforestation method and then to derive an attribute evaluation scheme relevant to the event-based transformation. The algorithm enables a more declarative style of development of event-based document transformers.