Effect of Readtable Case on the Lisp Reader (original) (raw)

The readtable case of the current readtable affects the _Lisp reader_in the following ways:

:upcase
When the readtable case is :upcase, unescaped constituent characters are converted to uppercase, as specified in Section 2.2 Reader Algorithm.
:downcase
When the readtable case is :downcase, unescaped constituent characters are converted to lowercase.
:preserve
When the readtable case is :preserve, the case of all characters remains unchanged.
:invert
When the readtable case is :invert, then if all of the unescaped letters in the extended token are of the same case, those (unescaped) letters are converted to the opposite case.