The HIDDEN attribute prevents information concerning a  constant
  definition   or   a   type,  variable,  procedure,  or  function
  declaration from being included in a generated environment file.
  The  HIDDEN  attribute  can  be  used  only  on  objects  at the
  outermost level of the compilation unit.

  It is possible to prevent all declarations within a  declaration
  section from being included in the environment file by preceding
  the reserved word CONST, TYPE, or VAR with the HIDDEN attribute.