Comments are areas of source code that the compiler ignores.  Commenting
your code is a good idea if you indend on anyone else working with it.  It
can also be useful for 'blocking out' an area of source code temporarily for
debugging, etc.  IPL has several ways of commenting code:

Enclose comments in "|" (pipe) characters.  These types of comments can span
multiple lines of source.  Any text in between pipes is ignored.

Any text after a "%" (percent sign) on that line is ignored by the compiler.

Any text after a "#" (number sign) on that line is ignored by the compiler,
but the # symbol MUST be the first character on the line (full line comment).

Some examples of commenting:

 | This is an enclosed comment.
      It can span multiple lines, and is useful
      for blocking out source code for debugging. |

 # here is an example of a line comment.
 # the next line contains a partial line comment ..
 @ int x = 10	  % declare integer x and assign it 10 ..

IPL supports embedded comments, that is, comments planted in the middle of
expressions.  This isn't a very pretty way to comment source, but it works.