Introduction

Swish - which stands for Semantic Web Inference Scripting in Haskell - was written by Graham Klyne as a framework, written in the purely functional programming language Haskell, for performing deductions in RDF data using a variety of techniques. Swish was conceived as a toolkit for experimenting with RDF inference, and for implementing stand-alone RDF file processors (usable in similar style to CWM, but with a view to being extensible in declarative style through added Haskell function and data value declarations). One of the aims was to explore Haskell as "a scripting language for the Semantic Web".

It was updated from version 0.2.1 by Vasili I Galchin so that it would build with the current version of GHC, and released on Hackage.

Since then it has been updated to take advantage of recent developments in the Haskell ecosystem, add support for the NTriples and Turtle serialisation formats, and a number of convenience functions. Development is done on GitLab at https://gitlab.com/dburke/swish and the previous bitbucket site is now outdated (you may also find a version on GitHub which should also be ignored).

I attempt to keep Swish buildable on recent GHC versions but it is done on a best-effort basis, so support for "older" versions of GHC is not guaranteed.

Aim

Current development is based on my own needs, which are more about using this as a RDF library for I/O with limited querying rather than for inferencing or use as a flexible graph-processing library (e.g. for extensions to non-RDF models).

Copyright

(c) 2003, 2004 G. Klyne
(c) 2009 Vasili I Galchin
(c) 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019,
    2020 Doug Burke

All rights reserved.

License

LGPL V2.1

Haskell and the Semantic Web

Other Haskell packages for RDF support include

• rdf4h
• hsparql
• hasparql-client

Installation

The following commands will install a command-line tool Swish along with the modules in the Swish namespace; documentation can be found on Hackage.

With cabal

Install a recent version of the Haskell platform and then try

% cabal update
% cabal install swish

With stack

Swish is available as part of the stackage curated package set.

There are several stack configuration files, for different GHC versions:

% cd swish
% stack install
% STACK_YAML=stack-8.8.yaml stack install
% STACK_YAML=stack-8.6.yaml stack install
% STACK_YAML=stack-8.4.yaml stack install
% STACK_YAML=stack-8.2.yaml stack install
% STACK_YAML=stack-8.0.yaml stack install
% STACK_YAML=stack-7.10.yaml stack install

With nix

There is now support for building with the nix package manager:

% nix-shell
...
nix-shell% cabal test

At the time of writing this uses GHC 8.8.2, but you can switch compiler

% nix-shell --argstr compiler ghc865