Null object: Difference between revisions

J doesn't have NULL. To indicate "missing data", "normal" data is usually pressed into service (e.g. <tt>0</tt> or <tt>_1</tt> in a numeric context, <tt>' '</tt> in a literal context, <tt>a:</tt> in a boxed context, etc). Most frequently, missing data is represented by the empty vector <tt><nowiki>''</nowiki></tt>.