Named disjunctions and lazy evaluation for syntactic ambiguities

Ambiguity is one of the main sources of complexity in natural language processing. We propose an original solution relying on the use of named disjunctions which are set of ordered formulae linked by a name. This representation is implemented within a constraint logic programming paradigm (allowing the use of underspecified structures) by means of lazy evaluation techniques. This approach avoids the expansion of the disjunctions into a normal form and allows one, in some cases, to compute a partial syntactic structure without disambiguating.