TDL---A Type Description Language for Constraint-Based Grammars.

Authors:

Hans-Ulrich Krieger, Ulrich Schäfer.

Task:

• linguistic analysis.
• test of linguistic theory (HPSG, FUG, PATR-II).
• as part of a deep NLP system.
• as part of a speech system.

Description:

TDL is a typed feature-based language, which is specifically designed to support highly lexicalized grammar theories, such as HPSG, FUG, or CUG. TDL offers the possibility to define (possibly recursive) types, consisting of type and feature constraints over the Boolean connectives AND, OR, and NOT, where the types are arranged in a subsumption hierarchy. TDL distinguishes between avm types (open-world reasoning) and sort types (closed-world reasoning) and allows the declaration of partitions and incompatible types. Working with partially and fully expanded types as well as with undefined types is possible, both at definition and at run time. TDL is incremental in that it allows the redefinition of types. Efficient reasoning is accomplished through specialized modules.

Extensibility:

program is extensible by experienced users.

Size:

• 20,000 lines of source code.
• 15 MB of executable.
• large grammars and lexicons for English, German, and Japanese.
  Implementation:
  Common Lisp.

  Platform:
  Unix.

  Status:
  • demonstration.
  • large research.
  • stable.
  • ongoing development.

  Contact:
  Hans-Ulrich Krieger

  Address:
  DFKI GmbH / Stuhlsatzenhausweg 3 / D-66123 Saarbruecken / Germany

  Telephone:
  +49 681 302 5299

  Email:
  krieger@dfki.de