Refactor out map.el usage

After some profiling, it turns out map-put and map-delete are 5-7x
slower (more on Emacs 25) than delq, setf/alist-get and add-to-list for
small lists (under 250 items), which is exactly how I've been using
them.

The only caveat is alist-get's signature is different on Emacs 25, thus
a polyfill is necessary in core-lib.

modules/feature/evil/config.el

@@ -231,12 +231,12 @@ variable for an explanation of the defaults (in comments). See
     (cons (format "(%s " (or (read-string "(") "")) ")"))
 
   ;; Add escaped-sequence support to embrace
-  (map-put (default-value 'embrace--pairs-list)
-           ?\\ (make-embrace-pair-struct
-                :key ?\\
-                :read-function #'+evil--embrace-escaped
-                :left-regexp "\\[[{(]"
-                :right-regexp "\\[]})]")))
+  (setf (alist-get ?\\ (default-value 'embrace--pairs-list))
+        (make-embrace-pair-struct
+         :key ?\\
+         :read-function #'+evil--embrace-escaped
+         :left-regexp "\\[[{(]"
+         :right-regexp "\\[]})]")))
 
 
 (def-package! evil-escape
@@ -332,8 +332,7 @@ the new algorithm is confusing, like in python or ruby."
   ;; Add custom commands to whitelisted commands
   (dolist (fn '(doom/backward-to-bol-or-indent doom/forward-to-last-non-comment-or-eol
                 doom/backward-kill-to-bol-and-indent))
-    (map-put evil-mc-custom-known-commands
-             fn '((:default . evil-mc-execute-default-call))))
+    (add-to-list 'evil-mc-custom-known-commands `(,fn (:default . evil-mc-execute-default-call))))
 
   ;; Activate evil-mc cursors upon switching to insert mode
   (defun +evil-mc|resume-cursors () (setq evil-mc-frozen nil))

modules/feature/file-templates/autoload.el

@@ -2,7 +2,9 @@
 
 (defun +file-templates--set (pred plist)
   (if (null (car-safe plist))
-      (setq +file-templates-alist (map-delete +file-templates-alist pred))
+      (setq +file-templates-alist
+            (delq (assoc pred +file-templates-alist)
+                  +file-templates-alist))
     (push `(,pred ,@plist) +file-templates-alist)))
 
 ;;;###autodef

modules/feature/lookup/autoload/devdocs.el

@@ -9,7 +9,7 @@ DOCSET (a string).
 See `devdocs-alist' for the defaults. "
   (after! (:when (boundp 'devdocs-alist))
     (dolist (mode (doom-enlist modes))
-      (map-put devdocs-alist mode docset))))
+      (setf (alist-get mode devdocs-alist) docset))))
 
 ;;;###autoload
 (def-setting! :devdocs (modes docset)

modules/feature/lookup/autoload/lookup.el

@@ -72,7 +72,7 @@ properties:
                       "Search on: "
                       (mapcar #'car +lookup-provider-url-alist)
                       nil t)))
-          (map-put +lookup--last-provider key provider)
+          (setf (alist-get +lookup--last-provider key) provider)
           provider))))
 
 (defun +lookup--symbol-or-region (&optional initial)
@@ -318,7 +318,9 @@ for the provider."
           (user-error "The search query is empty"))
         (funcall +lookup-open-url-fn (format url (url-encode-url search))))
     (error
-     (map-delete +lookup--last-provider major-mode)
+     (setq +lookup--last-provider
+           (delq (assq major-mode +lookup--last-provider)
+                 +lookup--last-provider))
      (signal (car e) (cdr e)))))
 
 ;;;###autoload

modules/feature/workspaces/config.el

@@ -30,7 +30,8 @@ stored in `persp-save-dir'.")
 ;; particularly useful for the `+workspace/restart-emacs-then-restore' command.
 (defun +workspaces-restore-last-session (&rest _)
   (add-hook 'emacs-startup-hook #'+workspace/load-session 'append))
-(map-put command-switch-alist "--restore" #'+workspaces-restore-last-session)
+(add-to-list 'command-switch-alist (cons "--restore" #'+workspaces-restore-last-session))
+
 
 ;;
 ;; Plugins
@@ -41,7 +42,9 @@ stored in `persp-save-dir'.")
   :init
   (defun +workspaces|init ()
     ;; Remove default buffer predicate so persp-mode can put in its own
-    (setq default-frame-alist (map-delete default-frame-alist 'buffer-predicate))
+    (setq default-frame-alist
+          (delq (assq 'buffer-predicate default-frame-alist)
+                default-frame-alist))
     (add-hook 'after-make-frame-functions #'+workspaces|init-frame)
     (require 'persp-mode)
     (unless (daemonp)