asterix-external-data/src/main/resources/schema/library.xsd

<?xml version="1.0" encoding="ISO-8859-1" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:lib="library" targetNamespace="library" elementFormDefault="qualified">

<!-- definition of simple types --> 
<xs:element name="language" type="xs:string"/>
<xs:element name="name" type="xs:string"/>
<xs:element name="arguments" type="xs:string"/>
<xs:element name="return_type" type="xs:string"/>
<xs:element name="function_type" type="xs:string"/>
<xs:element name="definition" type="xs:string"/>

<!-- definition of complex elements -->
<xs:element name="function">
  <xs:complexType>
    <xs:sequence>
      <xs:element ref="lib:name"/>
      <xs:element ref="lib:function_type"/>
      <xs:element ref="lib:arguments"/>
      <xs:element ref="lib:return_type"/>
      <xs:element ref="lib:definition"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

<xs:element name="functions">
  <xs:complexType>
    <xs:sequence>
      <xs:element ref="lib:function" maxOccurs="unbounded"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

<xs:element name="library">
  <xs:complexType>
    <xs:sequence>
      <xs:element ref="lib:language"/>
      <xs:element ref="lib:functions" minOccurs="0"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

</xs:schema>