comment-styles

comment-styles is a variable defined in `newcomment.el'.
Its value is shown below.

• This variable may be risky if used as a file-local variable.

Documentation:
Comment region style definitions.
Each style is defined with a form (STYLE . (MULTI ALIGN EXTRA INDENT DOC)).
DOC should succinctly describe the style.
STYLE should be a mnemonic symbol.
MULTI specifies that comments are allowed to span multiple lines.
e.g. in C it comments regions as
/* blabla
* bli */
rather than
/* blabla */
/* bli */
if `comment-end' is empty, this has no effect.

ALIGN specifies that the `comment-end' markers should be aligned.
e.g. in C it comments regions as
/* blabla */
/* bli */
rather than
/* blabla */
/* bli */
if `comment-end' is empty, this has no effect, unless EXTRA is also set,
in which case the comment gets wrapped in a box.

EXTRA specifies that an extra line should be used before and after the
region to comment (to put the `comment-end' and `comment-start').
e.g. in C it comments regions as
/*
* blabla
* bli
*/
rather than
/* blabla
* bli */
if the comment style is not multi line, this has no effect, unless ALIGN
is also set, in which case the comment gets wrapped in a box.

INDENT specifies that the `comment-start' markers should not be put at the
left margin but at the current indentation of the region to comment.
If INDENT is `multi-char', that means indent multi-character
comment starters, but not one-character comment starters.

Value:

((plain nil nil nil nil "Start in column 0 (do not indent), as in Emacs-20")
 (indent-or-triple nil nil nil multi-char "Start in column 0, but only for single-char starters")
 (indent nil nil nil t "Full comment per line, ends not aligned")
 (aligned nil t nil t "Full comment per line, ends aligned")
 (box nil t t t "Full comment per line, ends aligned, + top and bottom")
 (extra-line t nil t t "One comment for all lines, end on a line by itself")
 (multi-line t nil nil t "One comment for all lines, end on last commented line")
 (box-multi t t t t "One comment for all lines, + top and bottom"))