Function: whitespace-newline-mode

Toggle newline visualization (Whitespace Newline mode).
With a prefix argument ARG, enable Whitespace Newline mode if ARG
is positive, and disable it otherwise. If called from Lisp,
enable the mode if ARG is omitted or nil.

Use `whitespace-newline-mode' only for NEWLINE visualization
exclusively. For other visualizations, including NEWLINE
visualization together with (HARD) SPACEs and/or TABs, please,
use `whitespace-mode'.

See also `whitespace-newline' and `whitespace-display-mappings'. (fn &optional ARG)