Fortran mode has specialized support for Auto Fill mode, which is a
minor mode that automatically splits statements as you insert them
when they become too wide. Splitting a statement involves making
continuation lines using fortran-continuation-string
(see Continuation Lines). This splitting happens when you type
SPC, RET, or TAB, and also in the
Fortran indentation commands. You activate Auto Fill in Fortran mode
in the normal way.
See Auto Fill Mode.
Auto Fill breaks lines at spaces or delimiters when the lines get
longer than the desired width (the value of fill-column). The
delimiters (besides whitespace) that Auto Fill can break at are
‘+’, ‘-’, ‘/’, ‘*’, ‘=’, ‘<’, ‘>’,
and ‘,’. The line break comes after the delimiter if the
variable fortran-break-before-delimiters is nil.
Otherwise (and by default), the break comes before the delimiter.
To enable Auto Fill in all Fortran buffers, add
auto-fill-mode to fortran-mode-hook.
See Hooks.