Finite-state morphology in the general tradition of the Two-Level and Xerox implementations has proved very successful in the production of robust morphological analyzer-generators, including many large-scale commercial systems. However, it has long been recognized that these implementations have serious limitations in handling non-concatenative phenomena. We describe a new technique for constructing finitestate transducers that involves reapplying the regular-expression compiler to its own output. Implemented in an algorithm called compilereplace, this technique has proved useful for handling non-concatenative phenomena; and we demonstrate it on Malay full-stem reduplication and Arabic stem interdigitation.
Kenneth R. Beesley, Lauri Karttunen