Enable smart tabs for C and C++

config.org

@@ -323,7 +323,8 @@
      (setq-default basic-offset 4)
    #+end_src
 
-   And generally indenting with spaces is more common, so make that the default:
+   And generally indenting with spaces is more common, so make that
+   the default:
 
    #+begin_src emacs-lisp
      (setq-default indent-tabs-mode nil)
@@ -356,20 +357,49 @@
       (require 'lsp-ido)
     #+end_src
 
-** C
+*** Smart Tabs
-   For C there is =clangd= implementing LSP. Assuming that's installed
+    Indent with tabs and align with spaces. Installing the package
-   and on the =PATH=, we can just hook =lsp-mode= into the default
+    here but it's enabled on a per-language basis in the languages'
-   mode and there will be much rejoicing.
+    individual config sections.
 
-   #+begin_src emacs-lisp
+    #+begin_src emacs-lisp
-     (add-hook 'c-mode-hook #'lsp-deferred)
+      (use-package smart-tabs-mode)
-   #+end_src
+    #+end_src
+
+    [[help:smart-tabs-insinuate][smart-tabs-insinuate]] enables smart tabs for a particular language,
+    but also it will only be used when [[help:indent-tabs-mode][indent-tabs-mode]] is
+    non-nil. The following function wraps up setting
+    ~indent-tabs-mode~ and enabling smart tabs for the language into
+    one thing:
+
+    #+begin_src emacs-lisp
+      (defun enable-smart-tabs (lang hook)
+        "Enable smart tabs for lang (even if indent-tabs-mode is nil by default)"
+        (smart-tabs-insinuate lang)
+        (add-hook hook (lambda () (setq indent-tabs-mode nil))))
+    #+end_src
+
+** C
+    For C there is =clangd= implementing LSP. Assuming that's
+    installed and on the =PATH=, we can just hook =lsp-mode= into the
+    default mode and there will be much rejoicing.
+
+    #+begin_src emacs-lisp
+      (add-hook 'c-mode-hook #'lsp-deferred)
+    #+end_src
+
+    And we want to enable smart tabs:
+
+    #+begin_src emacs-lisp
+      (enable-smart-tabs 'c 'c-mode-hook)
+    #+end_src
 
 ** C++
-   Essentially the same story as for C
+   Essentially the same story as for C.
 
    #+begin_src emacs-lisp
      (add-hook 'c++-mode-hook #'lsp-deferred)
+     (enable-smart-tabs 'c++ 'c++-mode-hook)
    #+end_src
 
 ** Haskell