Function: c-newline-and-indent

c-newline-and-indent is a byte-compiled function defined in cc-cmds.el.gz.

Signature

(c-newline-and-indent &optional NEWLINE-ARG)

Documentation

Insert a newline and indent the new line.

This function fixes line continuation backslashes if inside a macro, and takes care to set the indentation before calling indent-according-to-mode, so that lineup functions like c-lineup-dont-change works better.

Source Code

;; Defined in /usr/src/emacs/lisp/progmodes/cc-cmds.el.gz
(defun c-newline-and-indent (&optional newline-arg)
  "Insert a newline and indent the new line.
This function fixes line continuation backslashes if inside a macro,
and takes care to set the indentation before calling
`indent-according-to-mode', so that lineup functions like
`c-lineup-dont-change' works better."

  ;; TODO: Backslashes before eol in comments and literals aren't
  ;; kept intact.
  (let ((c-macro-start (c-query-macro-start))
	;; Avoid calling c-backslash-region from c-indent-line if it's
	;; called during the newline call, which can happen due to
	;; c-electric-continued-statement, for example.  We also don't
	;; want any backslash alignment from indent-according-to-mode.
	(c-fix-backslashes nil)
	has-backslash insert-backslash
	start col)
    (save-excursion
      (beginning-of-line)
      (setq start (point))
      (while (and (looking-at "[ \t]*\\\\?$")
		  (= (forward-line -1) 0)))
      (setq col (current-indentation)))
    (when c-macro-start
      (if (and (eolp) (eq (char-before) ?\\))
	  (setq insert-backslash t
		has-backslash t)
	(setq has-backslash (eq (char-before (c-point 'eol)) ?\\))))
    (newline newline-arg)
    (indent-to col)
    (when c-macro-start
      (if insert-backslash
	  (progn
	    ;; The backslash stayed on the previous line.  Insert one
	    ;; before calling c-backslash-region, so that
	    ;; bs-col-after-end in it works better.  Fixup the
	    ;; backslashes on the newly inserted line.
	    (insert ?\\)
	    (backward-char)
	    (c-backslash-region (point) (point) nil t))
	;; The backslash moved to the new line, if there was any.  Let
	;; c-backslash-region fix a backslash on the previous line,
	;; and the one that might be on the new line.
	;; c-auto-align-backslashes is intentionally ignored here;
	;; maybe the moved backslash should be left alone if it's set,
	;; but we fix both lines on the grounds that the old backslash
	;; has been moved anyway and is now in a different context.
	(c-backslash-region start (if has-backslash (point) start) nil t)))
    (when c-syntactic-indentation
      ;; Reindent syntactically.  The indentation done above is not
      ;; wasted, since c-indent-line might look at the current
      ;; indentation.
      (let ((c-syntactic-context (c-save-buffer-state nil
				   (c-guess-basic-syntax))))
	;; We temporarily insert another line break, so that the
	;; lineup functions will see the line as empty.  That makes
	;; e.g. c-lineup-cpp-define more intuitive since it then
	;; proceeds to the preceding line in this case.
	(insert ?\n)
	(delete-horizontal-space)
	(setq start (- (point-max) (point)))
	(unwind-protect
	    (progn
	      (backward-char)
	      (indent-according-to-mode))
	  (goto-char (- (point-max) start))
	  (delete-char -1)))
      (when has-backslash
	;; Must align the backslash again after reindentation.  The
	;; c-backslash-region call above can't be optimized to ignore
	;; this line, since it then won't align correctly with the
	;; lines below if the first line in the macro is broken.
	(c-backslash-region (point) (point) nil t)))))