Move emacs/electric-indent to emacs/electric

This module will later be expanded to customize more of electric's
functionality.

modules/emacs/electric/autoload.el

@@ -0,0 +1,25 @@
+;;; emacs/electric/autoload.el -*- lexical-binding: t; -*-
+
+;;;###autodef
+(defun set-electric! (modes &rest plist)
+  "Declare :words (list of strings) or :chars (lists of chars) in MODES that
+trigger electric indentation."
+  (declare (indent 1))
+  (cl-destructuring-bind (&key char words) plist
+    (when (or chars words)
+      (let* ((name (mapconcat #'symbol-name modes "-"))
+             (fn (intern (format "+electric-indent--init-%s" name))))
+        (fset fn
+              (lambda () (electric-indent-local-mode +1)
+                (if chars (setq electric-indent-chars chars))
+                (if words (setq +electric-indent-words words))))
+        (dolist (mode modes)
+          (add-hook (intern (format "%s-hook" mode)) fn-name))))))
+
+;; FIXME obsolete :electric
+;;;###autoload
+(def-setting! :electric (modes &rest plist)
+  "Declare :words (list of strings) or :chars (lists of chars) in MODES that
+trigger electric indentation."
+  :obsolete set-electric!
+  `(set-electric! ,modes ,@plist))

modules/emacs/electric/config.el

@@ -0,0 +1,19 @@
+;;; emacs/electric/config.el -*- lexical-binding: t; -*-
+
+;; Smarter, keyword-based electric-indent
+
+(defvar-local +electric-indent-words '()
+  "The list of electric words. Typing these will trigger reindentation of the
+current line.")
+
+;;
+(after! electric
+  (setq-default electric-indent-chars '(?\n ?\^?))
+
+  (defun +electric-indent|char (_c)
+    (when (and (eolp) +electric-indent-words)
+      (save-excursion
+        (backward-word)
+        (looking-at-p (concat "\\<" (regexp-opt +electric-indent-words))))))
+  (add-to-list 'electric-indent-functions #'+electric-indent|char nil #'eq))
+