$               Substring comparison--binary               (Relational)
 %               Modulus--binary                            (Mathematical)
 &               Macro evaluation--unary                    (Special)
 ( )             Function or grouping indicator             (Special)
 *               Multiplication--binary                     (Mathematical)
 **              Exponentiation--binary                     (Mathematical)
 +               Addition, unary positive, concatenation    (Math, Character)
 ++              Increment--unary                           (Mathematical)
 -               Subtraction, unary negative, concatenation (Math, Character)
 --              Decrement--unary                           (Mathematical)
 ->              Alias assignment--binary                   (Special)
 .AND.           Logical AND--binary                        (Logical)
 .NOT.           Logical NOT--unary                         (Logical)
 .OR.            Logical OR--binary                         (Logical)
 /               Division--binary                           (Mathematical)
 :               Send--binary                               (Object)
 :=              Inline assign--binary                      (Assignment)
 <               Less than--binary                          (Relational)
 <=              Less than or equal--binary                 (Relational)
 <> != #         Not equal--binary                          (Relational)
 = (assign)      Simple assign--binary                      (Assignment)
 = (compound)    Compound assignment--binary                (Assignment)
 = (equality)    Equal--binary                              (Relational)
 ==              Exactly equal--binary                      (Relational)
 >               Greater than--binary                       (Relational)
 >=              Greater than or equal--binary              (Relational)
 @               Pass-by-reference--unary                   (Special)
 [ ]             Array element indicator                    (Special)
 { }             Literal array and code block delimiters    (Special)