<?xml version="1.0"?>

<xs:schema 
targetNamespace="http://www.ruleml.org/0.91/xsd"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
xmlns="http://www.ruleml.org/0.91/xsd"
elementFormDefault="qualified"
>

<!-- note that elementFormDefault is qualified because of local declarations -->

	<xs:annotation>
		<xs:documentation xml:lang="en">
			This is the XML Schema module for (strong) negation in RuleML.
			File: neg_module.xsd
			Version: 0.91
			Last Modification: 2006-07-17
			
			This module declares the following RuleML elements:
			* Neg
			* strong
			
			See http://www.ruleml.org/modularization for details about this modularization approach.
		</xs:documentation>
	</xs:annotation>

	<!--
		*** Neg ***
		A classical negation of a logical atom (i.e. classical or "strong" negation).

		See http://www.ruleml.org/0.91/glossary/#gloss-Neg

		content model: ( oid?, (strong | Atom) )
	-->
	<xs:attributeGroup name="Neg.attlist"/>
	<xs:group name="Neg.content">
		<xs:sequence>
			<xs:element ref="oid" minOccurs="0"/>
			<xs:choice>
				<xs:element ref="strong"/>		
				<xs:group ref="strong.content"/>
			</xs:choice>
		</xs:sequence>
	</xs:group>
	<xs:complexType name="Neg.type">
		<xs:group ref="Neg.content"/>
		<xs:attributeGroup ref="Neg.attlist"/>
	</xs:complexType>
	<xs:element name="Neg" type="Neg.type"/>

	<!--
		*** strong ***
		A role used for classical negation.

		See http://www.ruleml.org/0.91/glossary/#gloss-strong

		content model: ( Atom )
	-->
	<xs:attributeGroup name="strong.attlist"/>
	<xs:group name="strong.content">
		<xs:choice>
			<xs:element name="Atom" type="Atom.type"/>
		</xs:choice>
	</xs:group>
	<xs:complexType name="strong.type">
		<xs:group ref="strong.content"/>
		<xs:attributeGroup ref="strong.attlist"/>
	</xs:complexType>
	<xs:element name="strong" type="strong.type"/>
		
</xs:schema>
