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Reserved Words

This is a complete list of reserved identifiers in VHDL'87 and VHDL'93. These reserved identifers must not be used as user defined identifiers.
Identifiers with * are new to VHDL'93.
   abs                file                of                sll*
   access             for                 on                sra*
   after              function            open              srl*
   alias              generate            or                subtype
   all                generic             others            then
   and                group*              out               to
   architecture       guarded             package           transport
   array              if                  port              type
   assert             impure*             postponed*        unaffected*
   attribute          in                  procedure         units
   begin              inertial*           process           until
   block              inout               pure*             use
   body               is                  range             variable
   buffer             label               record            wait
   bus                library             register          when
   case               linkage             reject*           while
   component          literal*            rem               with
   configuration      loop                report*           xnor*
   constant           map                 return            xor
   disconnect         mod                 rol*
   downto             nand                ror*
   else               new                 select
   elsif              next                severity
   end                nor                 signal
   entity             not                 shared*
   exit               null                sla*