# RELAXNG non-XML grammar for RDFxt
# Jonathan Borden 3/7/2002
namespace local = ""
namespace rdf = "http://www.w3.org/1999/02/22-rdf-syntax-ns#"
namespace rdfx = "http://www.openhealth.org/RDF/RDFxtSyntax"
namespace c = "http://www.xml.gr.jp/xmlns/relaxngcc"
datatypes xsd = "http://www.w3.org/2001/XMLSchema-datatypes"

start = (RDF | RDFxt)

# handle rdf:RDF as RDF
RDF = element rdf:RDF{rdf:ID?,rdf1_bundle}
# extend other namespace qualified root elements with bundles
RDFxt = element * - (local:*,rdf:*){bundle}

# an RDF 1 bundle is a bag of statements
rdf1_bundle = desc*

# a bundle can be either sentences or rdf:Descriptions
bundle = 	(sentence|desc)*

# a sentence may have variables and 
# is considered like a function that accepts a bundle of arguments
# variables are not namespace qualified
sentence = 	element * - (local:*){var*,bundle}
var = 		element local:*{empty} | attribute local:*{""}
# an rdf:Description or typedNode
desc[c:class="desc"] = 		subject{predobj*}
subject[c:class="subject"] = 	
		element (* - (local:*,rdf:*)) | 
				rdf:Description |
				rdf:Alt|rdf:Seq|rdf:Bag 
			{
				(attribute rdf:about{
						anyURI [c:alias="subj"] >> <c:java> this.value = subj;</c:java>
					}|
				 attribute rdf:ID{xsd:NMTOKEN})?,
				 attribute bagID(xsd:NMTOKEN)?,
				 attribute rdf:type{anyURI}?
			}
predicate = (element * - (rdf:*,local:*)) | element rdf:li | element rdf:value
predobj = 	predicate{
				attribute rdf:ID{xsd:NMTOKEN}?,
				attribute rdf:bagID{xsd:NMTOKEN}?,
				obj | 
				attribute rdf:resource{anyURI} |
				(attribute rdf:parseType{"Resource"},obj+) |
				(attribute rdf:parseType{text - "Resource"}, any)
				} |
			predAttr
predAttr = 	attribute * - (local:*,rdf:*) | attribute rdf:value {text}
obj = 		subject | 
			text |
			RDF 
any =		mixed { element * { attribute * { text }*, any }* }