##### 9.28.3.1 Special Characters

The characters ``*`' and ``#`' are line comment characters; each start a comment at the beginning of a line, but only at the beginning of a line. A ``#`' prefixes a hexadecimal number if found elsewhere on a line. If a ``#`' appears at the start of a line the whole line is treated as a comment, but the line can also act as a logical line number directive (see Comments) or a preprocessor control command (see Preprocessing).

Two other characters, ``%`' and ``!`', each start a comment anywhere on the line. Thus you can't use the ``modulus`' and ``not`' operators in expressions normally associated with these two characters.

A ``;`' is a line separator, treated as a new-line, so separate instructions can be specified on a single line.