In this chapter an example is provided to illustrate the main features of the
package. In this example a stream class is defined to provide a wrapper for
which uses the Unicode Line Separator instead of the usual ASCII CR/LF combination to mark the end of lines in the file. Methods are then defined, specializing on the user defined stream class to ensure that it handles reading from and writing to a file correctly.
LispWorks User Guide and Reference Manual - 21 Dec 2011