This feature is obsolete: Don't use this feature anymore.
That's a 2.0 left-over that does not have any sense now that the type system is improved.
Just use Current instead.
Append in str the Eiffel coding of the character (Table in chapter 25 of ETL, page 423).%%%%%%%%
When the % letter notation exists, it is returned in priority: '%N' gives "%N", '%T'
gives "%T", etc.
When % letter notation does not exists (not in the ETL table), numbered coding is
used ("%/1/", "%/2/" etc).