(path-separator): Doc sync with 20.3.

(path-separator): Doc sync with 20.3.
(add-to-list): Ditto.
(buffer-live-p): Return bool value.
(cadr, cdar, cddr): New functions.
(save-current-buffer): Check whether orig-buffer is alive.
(functionp): Sync with 20.3; use `car-safe'.
(line-beginning-position, line-end-position): Simplified.
(point-at-bol, point-at-eol): Ditto.

(add-hook, remove-hook, make-local-hook): Removed;
require 'localhook instead.

(read-string): Don't use `eval-and-compile'.

(defmacro-maybe-cond): New macro.
(defun-maybe, defmacro-maybe, defsubst-maybe, defalias-maybe,
defvar-maybe, defconst-maybe, defun-maybe-cond): Return NAME.
(defun-maybe, defmacro-maybe, defsubst-maybe): Put edebug spec.
(defsubst): Moved to poe-18.el.