Content types come in pairs.  So while the type can be “text” and the subtype can be “pdf”, the complete content type cannot be “text/pdf”.  It can, however, be “text/html” or “application/pdf”.

So in my DFDL it’s not sufficient to specify enumerated lists for types and subtypes (as I have done below), I must also specify which types are allowed to go with which subtypes.

How would I do that, given this complexType?  TIA!

<xsd:complexType name="MimeTypeType">
<xsd:sequence dfdl:separator="/">
<xsd:element name="Type" dfdl:initiator="">
<xsd:annotation>
<xsd:appinfo source="http://www.ogf.org/dfdl/dfdl-1.0/">
<dfdl:assert test="{ dfdl:checkConstraints(.) }" message="The type must match one of the values on the enumerated list."/>
</xsd:appinfo>
</xsd:annotation>
<xsd:simpleType>
<xsd:restriction base="xsd:string">
<xsd:pattern
                            value="([a|A][p|P][p|P][l|L][i|I][c|C][a|A][t|T][i|I][o|O][n|N])|
                            ([m|M][u|U][l|L][t|T][i|I][p|P][a|A][r|R][t|T])|
                            ([m|M][e|E][s|S][s|S][a|A][g|G][e|E])|
                            ([t|T][e|E][x|X][t|T])"
/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
<xsd:element name="Subtype" dfdl:terminator="">
<xsd:annotation>
<xsd:appinfo source="http://www.ogf.org/dfdl/dfdl-1.0/">
<dfdl:assert test="{ dfdl:checkConstraints(.) }" message="The subtype must match one of the values on the enumerated list."/>
</xsd:appinfo>
</xsd:annotation>
<xsd:simpleType>
<xsd:restriction base="xsd:string">
<xsd:pattern
                            value="([p|P][d|D][f|F])|
                            ([a|A][l|L][t|T][e|E][r|R][n|N][a|A][t|T][i|I][v|V][e|E])|
                            ([m|M][i|I][x|X][e|E][d|D])|
                            ([r|R][f|F][c|C]822)|
                            ([p|P][l|L][a|A][i|I][n|N])|
                            ([h|H][t|T][m|M][l|L])"
/>
</xsd:restriction>
</xsd:simpleType>
</xsd:element>
</xsd:sequence>
</xsd:complexType>