slime-editing-commands provides some commands to
edit Lisp expressions.
Re-indents the current defun, or refills the current paragraph.
If point is inside a comment block, the text around point will be
treated as a paragraph and will be filled with
Otherwise, it will be treated as Lisp code, and the current defun
will be reindented. If the current defun has unbalanced parens,
an attempt will be made to fix it before reindenting.
Balance parentheses of open s-expressions at point. Insert enough right parentheses to balance unmatched left parentheses. Delete extra left parentheses. Reformat trailing parentheses Lisp-stylishly.
If REGION is true, operate on the region. Otherwise operate on the top-level sexp before point.
Insert a set of balanced comments around the s-expression containing the point. If this command is invoked repeatedly (without any other command occurring between invocations), the comment progressively moves outward over enclosing expressions. If invoked with a positive prefix argument, the s-expression arg expressions out is enclosed in a set of balanced comments.