
undefinedp(3)          C LIBRARY FUNCTIONS          undefinedp(3)

NAME
     undefinedp() - determine whether or not a given variable  is
     undefined.

SYNOPSIS
     int undefinedp(mixed arg);

DESCRIPTION
     Return 1 if `arg' is undefined.  'arg' will be undefined  in
     the following cases:

     1.   it is a variable set equal to the  return  value  of  a
          call_other   to  a  non-existent  method  (e.g.  arg  =
          call_other(obj, "???")).

     2.   it is a variable set equal to the return  value  of  an
          access  of  an  element in a mapping that doesn't exist
          (e.g. arg = map[not_there]).

SEE ALSO
     nullp(3),  mapp(3),  stringp(3),  pointerp(3),   objectp(3),
     intp(3).

Sun Release 4.1           Last change:                          1

