Expanding an undefined array

[Bernd Eggink]

Is the following difference intentional, a bug, or do I miss something?

  unset a
  set -- "${a[@]}"
  echo $#

Output: 0

  typeset a
  set -- "${a[@]}"
  echo $#

Output: 1

The man page says, "If the word is double-quoted, ... ${name[@]} expands 
each element of name to a separate word. When there are no array 
members, ${name[@]} expands  to  nothing." It doesn't mention a 
difference between an empty and an unset variable in this context. As a 
quoted 'nothing' normally counts 1 word, the 'nothing' in the first 
example appears to be some kind of 'super-nothing'.

Regards,
Bernd

--
Bernd Eggink
monoped@sudrala.de
http://sudrala.de