From e2a4c891c12e001e3851ef4cfcf05020f9cfef11 Mon Sep 17 00:00:00 2001
From: Ivan Malison <IvanMalison@gmail.com>
Date: Sat, 14 Jul 2018 12:51:22 -0700
Subject: [PATCH] [Emacs] Add major mode blacklisting macro

---
 dotfiles/emacs.d/README.org | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/dotfiles/emacs.d/README.org b/dotfiles/emacs.d/README.org
index bc56184d..bb264fee 100644
--- a/dotfiles/emacs.d/README.org
+++ b/dotfiles/emacs.d/README.org
@@ -933,6 +933,26 @@ This was stolen from https://github.com/jwiegley/dot-emacs
 (imalison:disable-mode-hook nlinum-mode)
 (imalison:disable-mode-hook yas-minor-mode)
 #+END_SRC
+** Add a blacklist to a major mode
+Sometimes a major mode's syntax highlighting can take a really long time to load
+in certain buffers. Usually you can just set a header to tell emacs not to run
+the major mode, but for cases where you can't always edit the file ahead of time
+this macro allows you to define a blacklist for your major mode that will
+prevent the major mode from being enabled on that file.
+#+begin_src emacs-lisp
+(defmacro imalison:add-blacklist-to-major (major-mode-fn-symbol)
+  (let ((blacklist-var-symbol (imalison:concat-symbols major-mode-fn-symbol "-blacklist"))
+        (check-blacklist-symbol (imalison:concat-symbols major-mode-fn-symbol "-check-blacklist")))
+    `(progn
+       (defvar ,blacklist-var-symbol nil)
+       (defun ,check-blacklist-symbol (mode-fn &rest args)
+         (unless (and (not (equal major-mode (quote ,major-mode-fn-symbol)))
+                      (equal nil args)
+                      (cl-loop for blacklist-regex in ,blacklist-var-symbol
+                               thereis (string-match blacklist-regex (buffer-name))))
+           (apply mode-fn args)))
+       (advice-add (quote ,major-mode-fn-symbol) :around (quote ,check-blacklist-symbol)))))
+#+end_src
 ** Other
 The stuff in this section is pretty crusty. I don't think its used anywhere, but
 I keep it around just in case I need it.