Most objects have more than one possible textual representation.
In general, from the point of view of the Lisp reader , wherever whitespace is permissible in a textual representation, any number of spaces and newlines can appear in standard syntax . When a function such as print produces a printed representation, it must choose from among many possible textual representations. In most cases, it chooses a program readable representation, but in certain cases it might use a more compact notation that is not program-readable. A number of option variables, called printer control variables , are provided to permit control of individual aspects of the printed representation of objects .