@hackage / XSaiga

An implementation of a polynomial-time top-down parser suitable for NLP

Latest1.7.0.0

About

Metadata

  • Last updated , by InBetweenNames
  • License BSD-3-Clause
  • Categories Parsers, Natural Language Processing, Text Processing

  • Maintained by: Shane Peelar <peelar@uwindsor.ca>

  • Lottery factor: 0

Links

Installation

Package Flags

Use the -f option with cabal commands to enable flags

    asterius (off by default)

    Use when building for Asterius -- sets up hooks for querying triplestores via XMLHttpRequest

    instore (off by default)

    Use built-in triplestore (no network access)

Readme

This package contains a Haskell implementation of the X-SAIGA project's parser combinators. The combinators enable fully-general attribute grammars to be implemented as executable specifications. Although the parser is top-down, and therefore highly modular, left-recursive productions are allowed and fully-general synthesized and inherited attribute dependencies are also allowed. The parse tree, which is decorated with attribute values, is built as a compact Tomita-style graph. Lazy evaluation enables attribute values to be evaluated only as needed. Time and space complexity are both O(n^4) where n is the length of the input. An example natural-language interface (called Solarman) to a semantic-web style RDF triplestore with approximately 3,000 facts about the solar system has been built as an executable specification of an attribute grammar. Solarman is included in this archive. Solarman computes answers to queries using an event-based denotational semantics which is based on Montague and Davidsonian semantics. A web site [3] has been created so that readers can enter queries and find out more about Solarman.

[1] http://cs.uwindsor.ca/~richard/PUBLICATIONS/PADL_08.pdf

[2] http://cs.uwindsor.ca/~richard/PUBLICATIONS/PADL_10.pdf

[3] http://speechweb2.cs.uwindsor.ca/solarman4/demo_sparql.html