Hyperion is written in XSB Prolog. The core parser is a very small and very general implementation of Clemens Lautemann's dynamic programming algorithm for parsing graphs using hyperedge replacement grammars.

This is a very early release of Hyperion, but I hope it will help the comprehesion of my results to see them in action.

**stars.P**, a grammar generating `stars', graphs with a central vertex and any number of spokes leaving it.**wheels.P**, a grammar generating `wheels', similar to the stars grammar, but now all `spoke' vertices are connected to their two neighbours.**pregroup.P**, a grammar for parsing pregroup grammars.**nldr.P**, a grammar for parsing multimodal categorial grammars. This particular grammar has two modes 0 and 1 interacting with the mixed associativity and mixed commutativity structural rules as described in my TAG+ paper.**lg.P**, a grammar for parsing Lambek-Grishin grammars with the type IV interaction rules.

Future releases will include more grammars, other graph parsing algorithms, a generally more efficient implementation and a better Dot/Graphviz interface.

Lautemann, C. (1990), The complexity of graph languages generated by
hyperedge replacement, Acta Informatica **27(5)**, pp. 399-421.

*This paper describes the graph parsing algorithm used by Hyperion
and analyses its complexity. Two conditions for polynomial parsing are
presented. Though we do not satisfy the conditions for componentwise
derivations, the limited *s*-separability condition gives us a polynomial
algorithm.
*

Moot, R. (2008), Lambek grammars, tree adjoining grammars and hyperedge replacement grammars, in C. Gardent & A. Sarkar, eds, `Proceedings of TAG+9, The ninth international workshop on tree adjoining grammars and related formalisms', pp. 65-72, (Proceedings Paper, Slides).

*This paper and the corresponding slides present the embedding
result between Tree Adjoining Grammars, Hyperedge Replacement Grammars
of order 2, multimodal categorial grammars and the Lambek-Grishin calculus.
*

Moot, R. (2008), `Lambek Grammars and Hyperedge Replacement Grammars', invited talk at Fifty Years of the Syntactic Calculus, 10-11 July 2008, Chieti (Slides).

*The slides of this invited talk are an extended version of my TAG+
talk, with more emphasis on parsing as done by Hyperion.*

Moot, R. (2008), `Lambek Grammars and Hyperedge Replacement Grammars' (Draft Report).

*This draft report spells out the correspondence between multimodal
categorial grammars, the Lambek-Grishin calculus and second-order
Hyperedge Replacement Grammars in more detail. It's work in progress
and some parts are still incomplete, so please do not cite, but I'd
welcome any comments you might have. *

Richard.Moot@labri.fr Last modified: Mon Sep 22 15:10:24 CEST 2008