internal override XmlSchemaDatatype DeriveByRestriction(XmlSchemaObjectCollection facets, XmlNameTable nameTable, XmlSchemaType schemaType)
{
DatatypeImplementation dt = (DatatypeImplementation)MemberwiseClone();
dt._restriction = this.FacetsChecker.ConstructRestriction(this, facets, nameTable);
dt._baseType = this;
dt._parentSchemaType = schemaType;
dt._valueConverter = null; //re-set old datatype's valueconverter
return dt;
}