Interactions between linguistic constraints: Procedural vs. declarative approaches

The traditional approach to generation is to derive a surface string from a semantic structure through various intermediate levels using a carefully ordered set of transformation steps. We show by some examples that this approach involves a lot of specific control decisions which cannot be generalized across several languages. We present a constraint-based approach where all levels of linguistic information are represented in a single structure. All levels introduce constraints on the linguistic structure stated as a set of feature type definitions. Relationships between levels are modelled as a set of (partial) relational constraints which apply simultaneously on all levels of the linguistic structure.Research reported in this paper is partly supported by the German Ministry of Research and Technology (BMFT, Bundesminister für Forschung und Technologie), under grant No. 08 B3116 3. The views and conclusions contained herein are those of the authors and should not be interpreted as representing official policies. We would like to thank John Bateman for his helpful comments on a previous version of this paper. The responsibility for all remaining errors resides, of course, with the authors.