// Allow subclassing for etch defined structs and externs.
if (n.isStruct() || n.isExcept())
return String.format( "Validator_custom.get( %s.class, %d, true )",
n.efqname( this ), type.dim() );
// Don't allow subclassing for externs or etch defined enums.
if (!(n.isExtern() || n.isEnumx()))
Assertion.check( n.isExtern() || n.isEnumx(),