Sarrif – The Elegant Arabic Morphology Parser

In this paper we present Sarrif, our Arabic Morphology Parser, featuring a novel approach to the description of Arabic morphology with 2-tape finite state transducers, based on a particular and systematic use of the operation of composition in a way that allows for incremental substitutions of concatenated lexical morpheme specifications with their surface realization for non-concatenative processes (the case of Arabic templatic interdigitation and non-templatic circumfixation). We argue that: 1. the method of incremental substitutions through compositions allows for an elegant description of all main morphological processes present in natural languages including non-concatenative ones in strict finite-state terms, without the need to resort to extensions of any sort; 2. our approach allows for the most logical encoding of every kind of dependency, including traditional long-distance ones (mutual exclusiveness), circumfixations and idiosyncratic root and pattern combinations; 3. a smart usage of composition such as ours allows for the creation of a same system that can be easily accomodated to fulfil the duties of both a stemmer (or lexicon development tool) and a full-fledged lexical transducer.