The other nested data types, SEQUENCE and CHOICE, are relatively trivial to convert once the columns have been assembled as described in the previous section. A single row may be used to output a message without repeating types.

The CHOICE data type bears some explanation. The following specification is the same used in the previous section:

   A ::= SEQUENCE {
      a INTEGER,
      b CHOICE { aa INTEGER, bb BOOLEAN },
      c BIT STRING
   }            
         

Some example output data follows:

   a,aa,bb,c            
   1,,FALSE,101010
   2,137,,100001
         

The output lines will contain data in either the aa or bb but not both. Only the selected data should be represented in the output line.