Compiling Typed Attribute-Value Logic Grammars

Abstract

The unification-based approach to processing attribute-value logic grammars, similar to Prolog interpretation, has become the standard. We propose an alternative, embodied in the Attribute-Logic Engine (ALE) (Carpenter 1993) , based on the Warren Abstract Machine (WAM) approach to compiling Prolog (Aït-Kaci 1991). Phrase structure grammars with procedural attachments, similar to Definite Clause Grammars (DCG) (Pereira — Warren 1980), are specified using a typed version of Rounds-Kasper logic (Carpenter 1992). We argue for the benefits of a strong and total version of typing in terms of both clarity and efficiency. Finally, we discuss the compilation of grammars into a few efficient low-level instructions for the basic feature structure operations.