I've just released a SPARQL 1.0 library for Ruby [1]. This version, while early, is fully compliant with DAWG data-r2 tests and is implemented in pure Ruby.
The gem parses SPARQL grammar to SPARQL S-Expressions (SSE) based on Jena ARQ's syntax [2]. This is then executed by RDF.rb [3] BGP query support. More on this in my blog post [4], and documentation [5] [1] http://rubygems.org/gems/sparql [2] http://jena.sourceforge.net/ARQ/algebra.html [3] http://rubygems.org/gems/rdf [4] http://greggkellogg.net/2011/10/03/sparql-1-0-for-ruby [5] http://rubydoc.info/github/gkellogg/sparql/master/frames
