<grammar datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes"
  xmlns="http://relaxng.org/ns/structure/1.0">

<start>
    <element name="gradebook">
        <ref name="taskDefinition"/>
        <oneOrMore>
            <element name="student">
                <ref name="studentDefinition"/>
            </element>
        </oneOrMore>
    </element>
</start>

<define name="taskDefinition">
    <element name="task-list">
        <zeroOrMore>
            <element name="task">
                <text />
                <attribute name="id">
                    <data type="ID"/>
                </attribute>
                <attribute name="type">
                    <choice>
                    <value type="string">homework</value>
                    <value type="string">lab</value>
                    <value type="string">project</value>
                    <value type="string">attendance</value>
                    <value type="string">extra-credit</value>
                    <value type="string">test</value>
                    <value type="string">quiz</value>
                    <value type="string">midterm</value>
                    <value type="string">final</value>
                    </choice>
                </attribute>
                <attribute name="weight">
                    <data type="decimal"/>
                </attribute>
                <attribute name="max">
                    <data type="decimal"/>
                </attribute>
                <attribute name="date">
                    <data type="date"/>
                </attribute>
                <optional>
                    <attribute name="recorded">
                        <choice>
                        <value type="string">yes</value>
                        <value type="string">no</value>
                        </choice>
                    </attribute>
                </optional>
            </element>
        </zeroOrMore>
    </element>
</define>

<define name="studentDefinition">
    <element name="last"><text/></element>
    <element name="first"><text/></element>
    <element name="email"><text/></element>
    <element name="info"><text/></element>
    <oneOrMore>
        <element name="result">
            <ref name="resultDefinition"/>
        </element>
    </oneOrMore>
    <attribute name="id">
        <data type="ID">
            <param name="pattern">S[0-9-]{9,11}</param>
        </data>
    </attribute>
</define>

<define name="resultDefinition">
    <text/>
    <attribute name="ref">
        <data type="IDREF"/>
    </attribute>
    <attribute name="score">
        <choice>
        <value type="string"></value>
        <data type="positiveInteger">
            <param name="maxInclusive">100</param>
        </data>
        </choice>
    </attribute>
</define>

</grammar>