Customizing indentation in makefile mode?

Question

In my makefiles, I prefer the following indentation for continuation lines:

FILES:=                \
    file1.cpp          \
    file2.cpp          \
    fileYetAnother.cpp

LIBS:=                 \
    libsth1.so         \
    libelsewhere.so

still, makefile mode indents it in the following way (when asked to reindent file or region):

FILES:=            \
file1.cpp          \
file2.cpp          \
fileYetAnother.cpp

LIBS:=             \
libsth1.so         \
libelsewhere.so

Is it possible to configure it somehow to use the former variant (= indent continuation lines by 4 spaces or tab) ?

What about `indent-according-to-mode` command? – Andrii Tykhonov Nov 06 '14 at 22:24 — Andrii Tykhonov, Nov 06 '14 at 22:24

score 2 · Accepted Answer · answered Nov 17 '14 at 11:03

2

Building on purple_arrows' solution:

(defun my-makefile-indent-line ()
  (save-excursion
(forward-line 0)
(cond
 ;; keep TABs
 ((looking-at "\t")
  t)
 ;; indent continuation lines to 4
 ((and (not (bobp))
       (= (char-before (1- (point))) ?\\))
  (delete-horizontal-space)
  (indent-to 4))
 ;; delete all other leading whitespace
 ((looking-at "\\s-+")
  (replace-match "")))))

(add-hook 'makefile-mode-hook
      (lambda ()
    (setq-local indent-line-function 'my-makefile-indent-line)))

answered Nov 17 '14 at 11:03

Alex Schröder

356
1
4

The only problem is that this will not work if your file list is indented by TABs, because my code leaves those untouched. – Alex Schröder Nov 17 '14 at 11:06
fix the indentation to 4 is not a good solution, what if the `FILES` and `LIBS` are long, and there is one element after `:=`, and you better align the following elements with the first one after `:=` ? – CodyChan Apr 29 '15 at 02:22
Four spaces is what the question asked. – Alex Schröder May 15 '15 at 19:46

purple_arrows · Answer 2 · 2014-11-07T06:26:07.310

0

Yes. It is possible to configure it, somehow.

(With apologies for the snark.)

Write a function that indents a line the way you want, then set that function as the value of the variable indent-line-function for makefile-mode. Something like:

(defun my-makefile-indent-line ()
  ...)

(add-hook 'makefile-mode-hook (lambda () (setq-local indent-line-function 'my-makefile-indent-line)))

edited Nov 07 '14 at 06:26

answered Nov 07 '14 at 06:13

purple_arrows

2,373
10
19

Well, those 3 dots are sth I am not sure how to fill... But thanks for partial pointer. – Mekk Nov 07 '14 at 09:23

Timm · Answer 3 · 2019-06-09T08:09:56.460

0

In case you're using aggressive-indent-mode, it helped me to put makefile-mode onto the list of aggressive-indent-excluded-modes:

(global-aggressive-indent-mode)
(add-to-list 'aggressive-indent-excluded-modes 'makefile-mode)

Note that this only works with global-aggressive-indent-mode turned on.

edited Jun 09 '19 at 08:09

answered Jun 09 '19 at 08:02

Timm

1,549
12
23

Customizing indentation in makefile mode?

3 Answers3

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