* emulation/edt-mapper.el (function-key-map):

(edt-map-key): Make it a function instead of using fset. Inline
edt-gnu-map-key and edt-lucid-map-key. Use featurep 'xemacs.
(edt-gnu-map-key, edt-lucid-map-key): Remove.
(edt-x-emacs-p): Remove.
(edt-emacs-variant, edt-window-system, edt-xserver):
Use featurep 'xemacs.

* net/eudc.el: Use (featurep 'xemacs) instead of the string test.
Replace eudc-xemacs-p with its definition.
(eudc-xemacs-p, eudc-emacs-p, eudc-xemacs-mule-p)
(eudc-emacs-mule-p): Remove.
(eudc-install-menu, eudc-mode): Replace eudc-emacs-p and
eudc-xemacs-p with feature tests.

* net/eudc-bob.el (eudc-bob-generic-menu, eudc-bob-mail-keymap)
(eudc-bob-url-keymap, eudc-bob-sound-keymap)
(eudc-bob-generic-keymap, eudc-bob-popup-menu)
(eudc-bob-toggle-inline-display):
* net/eudc-hotlist.el (eudc-hotlist-emacs-menu): Replace
eudc-emacs-p and eudc-xemacs-p with feature tests.

* net/eudcb-ph.el (eudc-ph-open-session): Replace
eudc-xemacs-mule-p with its former definition.

* progmodes/octave-mod.el (octave-xemacs-p): Remove.
(octave-abbrev-start): Replace octave-xemacs-p with
(featurep 'xemacs).

* progmodes/vera-mode.el (vera-xemacs): Remove.
(vera-mode-syntax-table): Replace vera-xemacs with
(featurep 'xemacs).

* progmodes/vhdl-mode.el (vhdl-xemacs): Remove.
(vhdl-doc-mode, vhdl-doc-variable, vhdl-compile-init)
(vhdl-speedbar-initialize, vhdl-ps-print-init)
(vhdl-forward-comment, vhdl-mode-map-init, vhdl-show-messages)
(vhdl-emacs-22, vhdl-emacs-21): Replace vhdl-xemacs
with (featurep 'xemacs).

* progmodes/antlr-mode.el (cond-emacs-xemacs-macfn, defunx)
(save-buffer-state-x):
* obsolete/fast-lock.el (fast-lock-verbose):
* emulation/viper-init.el (viper-xemacs-p)
(viper-cond-compile-for-xemacs-or-emacs):
* emacs-lisp/checkdoc.el (checkdoc-minor-mode-map):
* ps-print.el (case-fold-search):
* ediff-hook.el (ediff-cond-compile-for-xemacs-or-emacs):
* calculator.el (calculator-help): Use featurep 'xemacs.

16 files changed, 144 insertions, 115 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index e346d83e34d..f03f5cc953d 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,55 @@
 2007-10-21  Dan Nicolaescu  <dann@ics.uci.edu>
 
+        * emulation/edt-mapper.el (function-key-map):
+        (edt-map-key): Make it a function instead of using fset. Inline
+        edt-gnu-map-key and edt-lucid-map-key. Use featurep 'xemacs.
+        (edt-gnu-map-key, edt-lucid-map-key): Remove.
+        (edt-x-emacs-p): Remove.
+        (edt-emacs-variant, edt-window-system, edt-xserver): 
+        Use featurep 'xemacs.
+
+        * net/eudc.el: Use (featurep 'xemacs) instead of the string test.
+        Replace eudc-xemacs-p with its definition.
+        (eudc-xemacs-p, eudc-emacs-p, eudc-xemacs-mule-p)
+        (eudc-emacs-mule-p): Remove.
+        (eudc-install-menu, eudc-mode): Replace eudc-emacs-p and
+        eudc-xemacs-p with feature tests.
+
+        * net/eudc-bob.el (eudc-bob-generic-menu, eudc-bob-mail-keymap)
+        (eudc-bob-url-keymap, eudc-bob-sound-keymap)
+        (eudc-bob-generic-keymap, eudc-bob-popup-menu)
+        (eudc-bob-toggle-inline-display): 
+        * net/eudc-hotlist.el (eudc-hotlist-emacs-menu): Replace
+        eudc-emacs-p and eudc-xemacs-p with feature tests.
+
+        * net/eudcb-ph.el (eudc-ph-open-session): Replace
+        eudc-xemacs-mule-p with its former definition.
+
+        * progmodes/octave-mod.el (octave-xemacs-p): Remove.
+        (octave-abbrev-start): Replace octave-xemacs-p with 
+        (featurep 'xemacs).
+
+        * progmodes/vera-mode.el (vera-xemacs): Remove. 
+        (vera-mode-syntax-table): Replace vera-xemacs with 
+        (featurep 'xemacs).
+
+        * progmodes/vhdl-mode.el (vhdl-xemacs): Remove.
+        (vhdl-doc-mode, vhdl-doc-variable, vhdl-compile-init)
+        (vhdl-speedbar-initialize, vhdl-ps-print-init)
+        (vhdl-forward-comment, vhdl-mode-map-init, vhdl-show-messages)
+        (vhdl-emacs-22, vhdl-emacs-21): Replace vhdl-xemacs
+        with (featurep 'xemacs).
+
+        * progmodes/antlr-mode.el (cond-emacs-xemacs-macfn, defunx)
+        (save-buffer-state-x): 
+        * obsolete/fast-lock.el (fast-lock-verbose): 
+        * emulation/viper-init.el (viper-xemacs-p)
+        (viper-cond-compile-for-xemacs-or-emacs): 
+        * emacs-lisp/checkdoc.el (checkdoc-minor-mode-map): 
+        * ps-print.el (case-fold-search): 
+        * ediff-hook.el (ediff-cond-compile-for-xemacs-or-emacs): 
+        * calculator.el (calculator-help): Use featurep 'xemacs.
+
         * progmodes/prolog.el: Undo previous change.
         (comint-prompt-regexp, comint-process-echoes): Pacify
         byte-compiler.
diff --git a/lisp/calculator.el b/lisp/calculator.el
index 2676bedadba..aca37dd7cda 100644
--- a/lisp/calculator.el
+++ b/lisp/calculator.el
@@ -1715,7 +1715,7 @@ Used by `calculator-paste' and `get-register'."
         (use-global-map calculator-saved-global-map))
       (if (or (not calculator-electric-mode)
               ;; XEmacs has a problem with electric-describe-mode
-              (string-match "XEmacs" (emacs-version)))
+              (featurep 'xemacs))
         (describe-mode)
         (electric-describe-mode))
       (if calculator-electric-mode
diff --git a/lisp/ediff-hook.el b/lisp/ediff-hook.el
index 951abc20f73..00e6ba6bab2 100644
--- a/lisp/ediff-hook.el
+++ b/lisp/ediff-hook.el
@@ -53,10 +53,10 @@
 ;; compiler at hand (emacs or xemacs).
 ;; The autoload, below, is useless in Emacs because ediff-hook.el
 ;; is dumped with emacs, but it is needed in XEmacs
-;;;###autoload (defmacro ediff-cond-compile-for-xemacs-or-emacs (xemacs-form emacs-form) (if (string-match "XEmacs" emacs-version) xemacs-form emacs-form))
+;;;###autoload (defmacro ediff-cond-compile-for-xemacs-or-emacs (xemacs-form emacs-form) (if (featurep 'xemacs) xemacs-form emacs-form))
 
 (defmacro ediff-cond-compile-for-xemacs-or-emacs (xemacs-form emacs-form)
-  (if (string-match "XEmacs" emacs-version)
+  (if (featurep 'xemacs)
       xemacs-form emacs-form))
 
 ;; This autoload is useless in Emacs because ediff-hook.el is dumped with
diff --git a/lisp/emacs-lisp/checkdoc.el b/lisp/emacs-lisp/checkdoc.el
index edbf382f39e..185df6fbe43 100644
--- a/lisp/emacs-lisp/checkdoc.el
+++ b/lisp/emacs-lisp/checkdoc.el
@@ -1182,7 +1182,7 @@ generating a buffered list of errors."
     ;; Override some bindings
     (define-key map "\C-\M-x" 'checkdoc-eval-defun)
     (define-key map "\C-x`" 'checkdoc-continue)
-    (if (not (string-match "XEmacs" emacs-version))
+    (if (not (featurep 'xemacs))
         (define-key map [menu-bar emacs-lisp eval-buffer]
           'checkdoc-eval-current-buffer))
     ;; Add some new bindings under C-c ?
diff --git a/lisp/emulation/edt-mapper.el b/lisp/emulation/edt-mapper.el
index 9cf377f5645..484cfe58b3a 100644
--- a/lisp/emulation/edt-mapper.el
+++ b/lisp/emulation/edt-mapper.el
@@ -118,17 +118,17 @@
 ;;;  Decide Emacs Variant, GNU Emacs or XEmacs (aka Lucid Emacs).
 ;;;  Determine Window System, and X Server Vendor (if appropriate).
 ;;;
-(defconst edt-x-emacs-p (string-match "XEmacs" emacs-version)
+(defconst (featurep 'xemacs) (string-match "XEmacs" emacs-version)
   "Non-nil if we are running XEmacs version 19, or higher.")
 
-(defconst edt-emacs-variant (if edt-x-emacs-p "xemacs" "gnu")
+(defconst edt-emacs-variant (if (featurep 'xemacs) "xemacs" "gnu")
   "Indicates Emacs variant:  GNU Emacs or XEmacs \(aka Lucid Emacs\).")
 
-(defconst edt-window-system (if edt-x-emacs-p (console-type) window-system)
+(defconst edt-window-system (if (featurep 'xemacs) (console-type) window-system)
   "Indicates window system \(in GNU Emacs\) or console type \(in XEmacs\).")
 
 (defconst edt-xserver (if (eq edt-window-system 'x)
-                          (if edt-x-emacs-p
+                          (if (featurep 'xemacs)
                               ;; The Cygwin window manager has a `/' in its
                               ;; name, which breaks the generated file name of
                               ;; the custom key map file.  Replace `/' with a
@@ -245,7 +245,7 @@
 ;;;  function-key-map.
 ;;;
 (cond
- (edt-x-emacs-p
+ ((featurep 'xemacs)
   (setq edt-return-seq (read-key-sequence "Hit carriage-return <CR> to continue "))
   (setq edt-return (concat "[" (format "%s" (event-key (aref edt-return-seq 0))) "]")))
  (t
@@ -327,40 +327,37 @@
 ;;;
 ;;;  Key mapping functions
 ;;;
-(defun edt-lucid-map-key (ident descrip)
+(defun edt-map-key (ident descrip)
   (interactive)
-  (setq edt-key-seq (read-key-sequence (format "Press %s%s: " ident descrip)))
-  (setq edt-key (concat "[" (format "%s" (event-key (aref edt-key-seq 0))) "]"))
-  (cond ((not (equal edt-key edt-return))
-         (set-buffer "Keys")
-         (insert (format "    (\"%s\" . %s)\n" ident edt-key))
-         (set-buffer "Directions"))
-        ;; bogosity to get next prompt to come up, if the user hits <CR>!
-        ;; check periodically to see if this is still needed...
-        (t
-         (set-buffer "Keys")
-         (insert (format "    (\"%s\" . \"\" )\n" ident))
-         (set-buffer "Directions")))
+  (if (featurep 'xemacs)
+      (progn 
+        (setq edt-key-seq (read-key-sequence (format "Press %s%s: " ident descrip)))
+        (setq edt-key (concat "[" (format "%s" (event-key (aref edt-key-seq 0))) "]"))
+        (cond ((not (equal edt-key edt-return))
+               (set-buffer "Keys")
+               (insert (format "    (\"%s\" . %s)\n" ident edt-key))
+               (set-buffer "Directions"))
+              ;; bogosity to get next prompt to come up, if the user hits <CR>!
+              ;; check periodically to see if this is still needed...
+              (t
+               (set-buffer "Keys")
+               (insert (format "    (\"%s\" . \"\" )\n" ident))
+               (set-buffer "Directions"))))
+    (setq edt-key (read-key-sequence (format "Press %s%s: " ident descrip)))
+    (cond ((not (equal edt-key edt-return))
+           (set-buffer "Keys")
+           (insert (if (vectorp edt-key)
+                       (format "    (\"%s\" . %s)\n" ident edt-key)
+                     (format "    (\"%s\" . \"%s\")\n" ident edt-key)))
+           (set-buffer "Directions"))
+          ;; bogosity to get next prompt to come up, if the user hits <CR>!
+          ;; check periodically to see if this is still needed...
+          (t
+           (set-buffer "Keys")
+           (insert (format "    (\"%s\" . \"\" )\n" ident))
+           (set-buffer "Directions"))))
   edt-key)
 
-(defun edt-gnu-map-key (ident descrip)
-  (interactive)
-  (setq edt-key (read-key-sequence (format "Press %s%s: " ident descrip)))
-  (cond ((not (equal edt-key edt-return))
-         (set-buffer "Keys")
-         (insert (if (vectorp edt-key)
-                     (format "    (\"%s\" . %s)\n" ident edt-key)
-                   (format "    (\"%s\" . \"%s\")\n" ident edt-key)))
-         (set-buffer "Directions"))
-        ;; bogosity to get next prompt to come up, if the user hits <CR>!
-        ;; check periodically to see if this is still needed...
-        (t
-         (set-buffer "Keys")
-         (insert (format "    (\"%s\" . \"\" )\n" ident))
-         (set-buffer "Directions")))
-  edt-key)
-
-(fset 'edt-map-key (if edt-x-emacs-p 'edt-lucid-map-key 'edt-gnu-map-key))
 (set-buffer "Keys")
 (insert "
 ;;
@@ -494,7 +491,7 @@
 ;;;
 ;;;  Restore function-key-map.
 ;;;
-(if (and edt-window-system (not edt-x-emacs-p))
+(if (and edt-window-system (not (featurep 'xemacs)))
     (setq function-key-map edt-save-function-key-map))
 (setq EDT-key-name "")
 (while (not
diff --git a/lisp/emulation/viper-init.el b/lisp/emulation/viper-init.el
index 2b0e886b9cb..1b05ef7189d 100644
--- a/lisp/emulation/viper-init.el
+++ b/lisp/emulation/viper-init.el
@@ -50,7 +50,7 @@
   (message "Viper version is %s" viper-version))
 
 ;; Is it XEmacs?
-(defconst viper-xemacs-p (string-match "XEmacs" emacs-version))
+(defconst viper-xemacs-p (featurep 'xemacs))
 ;; Is it Emacs?
 (defconst viper-emacs-p (not viper-xemacs-p))
 ;; Tell whether we are running as a window application or on a TTY
@@ -61,7 +61,7 @@
 ;; compiler at hand.
 ;; Suggested by rms.
 (defmacro viper-cond-compile-for-xemacs-or-emacs (xemacs-form emacs-form)
-  (if (string-match "XEmacs" emacs-version)
+  (if (featurep 'xemacs)
       xemacs-form emacs-form))
 
 
diff --git a/lisp/net/eudc-bob.el b/lisp/net/eudc-bob.el
index f3b9baa13bc..1ba6f4a0927 100644
--- a/lisp/net/eudc-bob.el
+++ b/lisp/net/eudc-bob.el
@@ -149,7 +149,7 @@ display a button."
   "Toggle inline display of an image."
   (interactive)
   (when (eudc-bob-can-display-inline-images)
-    (cond (eudc-xemacs-p
+    (cond ((featurep 'xemacs)
            (let ((overlays (append (overlays-at (1- (point)))
                                    (overlays-at (point))))
                  overlay glyph)
@@ -266,7 +266,7 @@ display a button."
   (interactive "@e")
   (run-hooks 'activate-menubar-hook)
   (eudc-jump-to-event event)
-  (if eudc-xemacs-p
+  (if (featurep 'xemacs)
       (progn
         (run-hooks 'activate-popup-menu-hook)
         (popup-menu (eudc-bob-menu)))
@@ -282,7 +282,7 @@ display a button."
       (let ((map (make-sparse-keymap)))
         (define-key map "s" 'eudc-bob-save-object)
         (define-key map "!" 'eudc-bob-pipe-object-to-external-program)
-        (define-key map (if eudc-xemacs-p
+        (define-key map (if (featurep 'xemacs)
                             [button3]
                           [down-mouse-3]) 'eudc-bob-popup-menu)
         map))
@@ -295,7 +295,7 @@ display a button."
 (setq eudc-bob-sound-keymap
       (let ((map (make-sparse-keymap)))
         (define-key map [return] 'eudc-bob-play-sound-at-point)
-        (define-key map (if eudc-xemacs-p
+        (define-key map (if (featurep 'xemacs)
                             [button2]
                           [down-mouse-2]) 'eudc-bob-play-sound-at-mouse)
         map))
@@ -303,7 +303,7 @@ display a button."
 (setq eudc-bob-url-keymap
       (let ((map (make-sparse-keymap)))
         (define-key map [return] 'browse-url-at-point)
-        (define-key map (if eudc-xemacs-p
+        (define-key map (if (featurep 'xemacs)
                             [button2]
                           [down-mouse-2]) 'browse-url-at-mouse)
         map))
@@ -311,7 +311,7 @@ display a button."
 (setq eudc-bob-mail-keymap
       (let ((map (make-sparse-keymap)))
         (define-key map [return] 'goto-address-at-point)
-        (define-key map (if eudc-xemacs-p
+        (define-key map (if (featurep 'xemacs)
                             [button2]
                           [down-mouse-2]) 'goto-address-at-mouse)
         map))
@@ -319,20 +319,19 @@ display a button."
 (set-keymap-parent eudc-bob-image-keymap eudc-bob-generic-keymap)
 (set-keymap-parent eudc-bob-sound-keymap eudc-bob-generic-keymap)
 
-(if eudc-emacs-p
-    (progn
-      (easy-menu-define eudc-bob-generic-menu
-                        eudc-bob-generic-keymap
-                        ""
-                        eudc-bob-generic-menu)
-      (easy-menu-define eudc-bob-image-menu
-                        eudc-bob-image-keymap
-                        ""
-                        eudc-bob-image-menu)
-      (easy-menu-define eudc-bob-sound-menu
-                        eudc-bob-sound-keymap
-                        ""
-                        eudc-bob-sound-menu)))
+(when (not (featurep 'xemacs))
+  (easy-menu-define eudc-bob-generic-menu
+    eudc-bob-generic-keymap
+    ""
+    eudc-bob-generic-menu)
+  (easy-menu-define eudc-bob-image-menu
+    eudc-bob-image-keymap
+    ""
+    eudc-bob-image-menu)
+  (easy-menu-define eudc-bob-sound-menu
+    eudc-bob-sound-keymap
+    ""
+    eudc-bob-sound-menu))
 
 ;;;###autoload
 (defun eudc-display-generic-binary (data)
diff --git a/lisp/net/eudc-hotlist.el b/lisp/net/eudc-hotlist.el
index 2914ebdc1b0..5308bb2db1f 100644
--- a/lisp/net/eudc-hotlist.el
+++ b/lisp/net/eudc-hotlist.el
@@ -190,11 +190,11 @@ These are the special commands of this mode:
     ["Save and Quit" eudc-hotlist-quit-edit t]
     ["Exit without Saving" kill-this-buffer t]))
 
-(if eudc-emacs-p
-    (easy-menu-define eudc-hotlist-emacs-menu
-                      eudc-hotlist-mode-map
-                      ""
-                      eudc-hotlist-menu))
+(when (not (featurep 'xemacs))
+  (easy-menu-define eudc-hotlist-emacs-menu
+    eudc-hotlist-mode-map
+    ""
+    eudc-hotlist-menu))
 
 ;;; arch-tag: 9b633ab3-6a6e-4b46-b12e-d96739a7e0e8
 ;;; eudc-hotlist.el ends here
diff --git a/lisp/net/eudc.el b/lisp/net/eudc.el
index 0f300c20736..f43b37187f7 100644
--- a/lisp/net/eudc.el
+++ b/lisp/net/eudc.el
@@ -66,13 +66,6 @@
 
 ;;{{{      Internal variables and compatibility tricks
 
-(defconst eudc-xemacs-p (string-match "XEmacs" emacs-version))
-(defconst eudc-emacs-p (not eudc-xemacs-p))
-(defconst eudc-xemacs-mule-p (and eudc-xemacs-p
-                                  (featurep 'mule)))
-(defconst eudc-emacs-mule-p (and eudc-emacs-p
-                                 (featurep 'mule)))
-
 (defvar eudc-form-widget-list nil)
 (defvar eudc-mode-map nil)
 
@@ -670,7 +663,7 @@ These are the special commands of EUDC mode:
   (setq major-mode 'eudc-mode)
   (setq mode-name "EUDC")
   (use-local-map eudc-mode-map)
-  (if eudc-emacs-p
+  (if (not (featurep 'xemacs))
       (easy-menu-define eudc-emacs-menu eudc-mode-map "" (eudc-menu))
     (setq mode-popup-menu (eudc-menu)))
   (run-mode-hooks 'eudc-mode-hook))
@@ -1186,9 +1179,9 @@ queries the server for the existing fields and displays a corresponding form."
 
 (defun eudc-install-menu ()
   (cond
-   ((and eudc-xemacs-p (featurep 'menubar))
+   ((and (featurep 'xemacs) (featurep 'menubar))
     (add-submenu '("Tools") (eudc-menu)))
-   (eudc-emacs-p
+   ((not (featurep 'xemacs))
     (cond
      ((fboundp 'easy-menu-create-menu)
       (define-key
@@ -1236,7 +1229,7 @@ This does nothing except loading eudc by autoload side-effect."
   nil)
 
 ;;;###autoload
-(cond ((not (string-match "XEmacs" emacs-version))
+(cond ((not (featurep 'xemacs))
        (defvar eudc-tools-menu (make-sparse-keymap "Directory Search"))
        (fset 'eudc-tools-menu (symbol-value 'eudc-tools-menu))
        (define-key eudc-tools-menu [phone]
@@ -1267,7 +1260,7 @@ This does nothing except loading eudc by autoload side-effect."
                       ["Get Email" eudc-get-email t]
                       ["Get Phone" eudc-get-phone t])))
          (if (not (featurep 'eudc-autoloads))
-             (if eudc-xemacs-p
+             (if (featurep 'xemacs)
                  (if (and (featurep 'menubar)
                           (not (featurep 'infodock)))
                      (add-submenu '("Tools") menu))
diff --git a/lisp/net/eudcb-ph.el b/lisp/net/eudcb-ph.el
index 373b015b07e..5fed37f90a1 100644
--- a/lisp/net/eudcb-ph.el
+++ b/lisp/net/eudcb-ph.el
@@ -179,7 +179,7 @@ SERVER is either a string naming the server or a list (NAME PORT)."
         (set-buffer eudc-ph-process-buffer)
         (erase-buffer)
         (setq eudc-ph-read-point (point))
-        (and eudc-xemacs-mule-p
+        (and (featurep 'xemacs) (featurep 'mule)
              (set-buffer-file-coding-system 'binary t)))
       (setq process (open-network-stream "ph" eudc-ph-process-buffer host port))
       (if (null process)
diff --git a/lisp/obsolete/fast-lock.el b/lisp/obsolete/fast-lock.el
index dd33fe0b461..e2fb338242f 100644
--- a/lisp/obsolete/fast-lock.el
+++ b/lisp/obsolete/fast-lock.el
@@ -337,7 +337,7 @@ If a number, only buffers greater than this size have processing messages."
   :group 'fast-lock)
 
 (defvar fast-lock-save-faces
-  (when (save-match-data (string-match "XEmacs" (emacs-version)))
+  (when (featurep 'xemacs)
     ;; XEmacs uses extents for everything, so we have to pick the right ones.
     font-lock-face-list)
   "Faces that will be saved in a Font Lock cache file.
diff --git a/lisp/progmodes/antlr-mode.el b/lisp/progmodes/antlr-mode.el
index 594b628ad44..01f1c86618c 100644
--- a/lisp/progmodes/antlr-mode.el
+++ b/lisp/progmodes/antlr-mode.el
@@ -99,7 +99,7 @@
       (and (eq (car args) :@) (null msg) ; (:@ ...spliced...)
            (setq args (cdr args)
                  msg "(:@ ....) must return exactly one element"))
-      (let ((ignore (if (string-match "XEmacs" emacs-version) :EMACS :XEMACS))
+      (let ((ignore (if (featurep 'xemacs) :EMACS :XEMACS))
             (mode :BOTH) code)
         (while (consp args)
           (if (memq (car args) '(:EMACS :XEMACS :BOTH)) (setq mode (pop args)))
@@ -115,7 +115,7 @@
   ;; existing functions when they are `fboundp', provide shortcuts if they are
   ;; known to be defined in a specific Emacs branch (for short .elc)
   (defmacro defunx (name arglist &rest definition)
-    (let ((xemacsp (string-match "XEmacs" emacs-version)) reuses)
+    (let ((xemacsp (featurep 'xemacs)) reuses)
       (while (memq (car definition)
                    '(:try :emacs-and-try :xemacs-and-try))
         (if (eq (pop definition) (if xemacsp :xemacs-and-try :emacs-and-try))
@@ -152,7 +152,7 @@
   (defmacro ignore-errors-x (&rest body)
     (let ((specials '((scan-sexps . 4) (scan-lists . 5)))
           spec nils)
-      (if (and (string-match "XEmacs" emacs-version)
+      (if (and (featurep 'xemacs)
                (null (cdr body)) (consp (car body))
                (setq spec (assq (caar body) specials))
                (>= (setq nils (- (cdr spec) (length (car body)))) 0))
@@ -166,7 +166,7 @@
       `(let ((,modified (buffer-modified-p)))
          (unwind-protect
              (let ((buffer-undo-list t) (inhibit-read-only t)
-                   ,@(unless (string-match "XEmacs" emacs-version)
+                   ,@(unless (featurep 'xemacs)
                        '((inhibit-point-motion-hooks t) deactivate-mark))
                    before-change-functions after-change-functions
                    buffer-file-name buffer-file-truename)
diff --git a/lisp/progmodes/octave-mod.el b/lisp/progmodes/octave-mod.el
index b7084950a09..a0d33f56ee4 100644
--- a/lisp/progmodes/octave-mod.el
+++ b/lisp/progmodes/octave-mod.el
@@ -621,9 +621,6 @@ the end keyword."
     (delete-horizontal-space)
     (insert (concat " " octave-continuation-string))))
 
-(defvar octave-xemacs-p
-  (string-match "XEmacs\\|Lucid" emacs-version))
-
 ;;; Comments
 (defun octave-comment-region (beg end &optional arg)
   "Comment or uncomment each line in the region as Octave code.
@@ -1341,7 +1338,7 @@ Note that all Octave mode abbrevs start with a grave accent."
       (self-insert-command 1)
     (let (c)
       (insert last-command-char)
-      (if (if octave-xemacs-p
+      (if (if (featurep 'xemacs)
               (or (eq (event-to-character (setq c (next-event))) ??)
                   (eq (event-to-character c) help-char))
             (or (eq (setq c (read-event)) ??)
diff --git a/lisp/progmodes/vera-mode.el b/lisp/progmodes/vera-mode.el
index 9aaee22b9a9..11f47b40592 100644
--- a/lisp/progmodes/vera-mode.el
+++ b/lisp/progmodes/vera-mode.el
@@ -77,10 +77,6 @@
 
 ;;; Code:
 
-;; XEmacs handling
-(defconst vera-xemacs (string-match "XEmacs" emacs-version)
-  "Non-nil if XEmacs is used.")
-
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;; Variables
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -231,7 +227,7 @@ If nil, TAB always indents current line."
     (modify-syntax-entry ?\{ "(}"   syntax-table)
     (modify-syntax-entry ?\} "){"   syntax-table)
     ;; comment
-    (if vera-xemacs
+    (if (featurep 'xemacs)
         (modify-syntax-entry ?\/ ". 1456" syntax-table) ; XEmacs
       (modify-syntax-entry ?\/ ". 124b" syntax-table)) ; Emacs
     (modify-syntax-entry ?\* ". 23" syntax-table)
@@ -600,7 +596,7 @@ Key bindings:
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 
 ;; XEmacs compatibility
-(when vera-xemacs
+(when (featurep 'xemacs)
   (require 'font-lock)
   (copy-face 'font-lock-reference-face 'font-lock-constant-face)
   (copy-face 'font-lock-preprocessor-face 'font-lock-builtin-face))
diff --git a/lisp/progmodes/vhdl-mode.el b/lisp/progmodes/vhdl-mode.el
index 60d30eb8a6d..df315e4f46e 100644
--- a/lisp/progmodes/vhdl-mode.el
+++ b/lisp/progmodes/vhdl-mode.el
@@ -125,13 +125,10 @@
 
 ;;; Code:
 
-;; XEmacs handling
-(defconst vhdl-xemacs (string-match "XEmacs" emacs-version)
-  "Non-nil if XEmacs is used.")
 ;; Emacs 21+ handling
-(defconst vhdl-emacs-21 (and (<= 21 emacs-major-version) (not vhdl-xemacs))
+(defconst vhdl-emacs-21 (and (<= 21 emacs-major-version) (not (featurep 'xemacs)))
   "Non-nil if GNU Emacs 21, 22, ... is used.")
-(defconst vhdl-emacs-22 (and (<= 22 emacs-major-version) (not vhdl-xemacs))
+(defconst vhdl-emacs-22 (and (<= 22 emacs-major-version) (not (featurep 'xemacs)))
   "Non-nil if GNU Emacs 22, ... is used.")
 
 (defvar compilation-file-regexp-alist)
@@ -1844,13 +1841,13 @@ NOTE: Activate the new setting in a VHDL buffer by using the menu entry
 
 ;; add related general customizations
 (custom-add-to-group 'vhdl-related 'hideshow 'custom-group)
-(if vhdl-xemacs
+(if (featurep 'xemacs)
     (custom-add-to-group 'vhdl-related 'paren-mode 'custom-variable)
   (custom-add-to-group 'vhdl-related 'paren-showing 'custom-group))
 (custom-add-to-group 'vhdl-related 'ps-print 'custom-group)
 (custom-add-to-group 'vhdl-related 'speedbar 'custom-group)
 (custom-add-to-group 'vhdl-related 'line-number-mode 'custom-variable)
-(unless vhdl-xemacs
+(unless (featurep 'xemacs)
   (custom-add-to-group 'vhdl-related 'transient-mark-mode 'custom-variable))
 (custom-add-to-group 'vhdl-related 'user-full-name 'custom-variable)
 (custom-add-to-group 'vhdl-related 'mail-host-address 'custom-variable)
@@ -2093,7 +2090,7 @@ Ignore byte-compiler warnings you might see."
       newstr)))
 
 ;; `itimer.el': idle timer bug fix in version 1.09 (XEmacs 21.1.9)
-(when (and vhdl-xemacs (string< itimer-version "1.09")
+(when (and (featurep 'xemacs) (string< itimer-version "1.09")
            (not noninteractive))
   (load "itimer")
   (when (string< itimer-version "1.09")
@@ -2486,7 +2483,7 @@ conversion."
 (defun vhdl-show-messages ()
   "Get *Messages* buffer to show recent messages."
   (interactive)
-  (display-buffer (if vhdl-xemacs " *Message-Log*" "*Messages*")))
+  (display-buffer (if (featurep 'xemacs) " *Message-Log*" "*Messages*")))
 
 (defun vhdl-use-direct-instantiation ()
   "Return whether direct instantiation is used."
@@ -2686,7 +2683,7 @@ STRING are replaced by `-' and substrings are converted to lower case."
   (define-key vhdl-mode-map "\M-\C-u"      'vhdl-backward-up-list)
   (define-key vhdl-mode-map "\M-\C-a"      'vhdl-backward-same-indent)
   (define-key vhdl-mode-map "\M-\C-e"      'vhdl-forward-same-indent)
-  (unless vhdl-xemacs ; would override `M-backspace' in XEmacs
+  (unless (featurep 'xemacs) ; would override `M-backspace' in XEmacs
     (define-key vhdl-mode-map "\M-\C-h"    'vhdl-mark-defun))
   (define-key vhdl-mode-map "\M-\C-q"      'vhdl-indent-sexp)
   (define-key vhdl-mode-map "\M-^"         'vhdl-delete-indentation)
@@ -2713,7 +2710,7 @@ STRING are replaced by `-' and substrings are converted to lower case."
   (define-key vhdl-mode-map "\C-c\C-p\C-i" 'vhdl-port-paste-instance)
   (define-key vhdl-mode-map "\C-c\C-p\C-s" 'vhdl-port-paste-signals)
   (define-key vhdl-mode-map "\C-c\C-p\M-c" 'vhdl-port-paste-constants)
-  (if vhdl-xemacs ; `... C-g' not allowed in XEmacs
+  (if (featurep 'xemacs) ; `... C-g' not allowed in XEmacs
       (define-key vhdl-mode-map "\C-c\C-p\M-g" 'vhdl-port-paste-generic-map)
     (define-key vhdl-mode-map "\C-c\C-p\C-g" 'vhdl-port-paste-generic-map))
   (define-key vhdl-mode-map "\C-c\C-p\C-z" 'vhdl-port-paste-initializations)
@@ -5395,7 +5392,7 @@ negative, skip forward otherwise."
       (skip-chars-forward " \t\n"))))
 
 ;; XEmacs hack: work around buggy `forward-comment' in XEmacs 21.4+
-(unless (and vhdl-xemacs (string< "21.2" emacs-version))
+(unless (and (featurep 'xemacs) (string< "21.2" emacs-version))
   (defalias 'vhdl-forward-comment 'forward-comment))
 
 ;; This is the best we can do in Win-Emacs.
@@ -13013,7 +13010,7 @@ This does background highlighting of translate-off regions.")
 
 (defun vhdl-ps-print-init ()
   "Initialize postscript printing."
-  (if vhdl-xemacs
+  (if (featurep 'xemacs)
       (when (boundp 'ps-print-color-p)
         (vhdl-ps-print-settings))
     (make-local-variable 'ps-print-hook)
@@ -14064,10 +14061,10 @@ if required."
           (save-excursion (beginning-of-line) (looking-at "[0-9]+:"))]
          ["Rescan Directory" vhdl-speedbar-rescan-hierarchy
           :active (save-excursion (beginning-of-line) (looking-at "[0-9]+:"))
-          ,(if vhdl-xemacs :active :visible) (not vhdl-speedbar-show-projects)]
+          ,(if (featurep 'xemacs) :active :visible) (not vhdl-speedbar-show-projects)]
          ["Rescan Project" vhdl-speedbar-rescan-hierarchy
           :active (save-excursion (beginning-of-line) (looking-at "[0-9]+:"))
-          ,(if vhdl-xemacs :active :visible) vhdl-speedbar-show-projects]
+          ,(if (featurep 'xemacs) :active :visible) vhdl-speedbar-show-projects]
          ["Save Caches" vhdl-save-caches vhdl-updated-project-list])))
     ;; hook-ups
     (speedbar-add-expansion-list
@@ -16189,7 +16186,7 @@ no project is defined."
                     (assoc (car sublist) regexp-alist))
           (setq regexp-alist (cons (list (nth 0 sublist)
                                          (if (= 0 (nth 1 sublist))
-                                             (if vhdl-xemacs 9 nil)
+                                             (if (featurep 'xemacs) 9 nil)
                                            (nth 1 sublist))
                                          (nth 2 sublist) (nth 3 sublist))
                                    regexp-alist)))
@@ -16989,7 +16986,7 @@ to visually support naming conventions.")
 (defun vhdl-doc-variable (variable)
   "Display VARIABLE's documentation in *Help* buffer."
   (interactive)
-  (unless vhdl-xemacs
+  (unless (featurep 'xemacs)
     (help-setup-xref (list #'vhdl-doc-variable variable) (interactive-p)))
   (with-output-to-temp-buffer
       (if (fboundp 'help-buffer) (help-buffer) "*Help*")
@@ -17001,7 +16998,7 @@ to visually support naming conventions.")
 (defun vhdl-doc-mode ()
   "Display VHDL Mode documentation in *Help* buffer."
   (interactive)
-  (unless vhdl-xemacs
+  (unless (featurep 'xemacs)
     (help-setup-xref (list #'vhdl-doc-mode) (interactive-p)))
   (with-output-to-temp-buffer
       (if (fboundp 'help-buffer) (help-buffer) "*Help*")
diff --git a/lisp/ps-print.el b/lisp/ps-print.el
index a8633b9a75f..49b0960f9bb 100644
--- a/lisp/ps-print.el
+++ b/lisp/ps-print.el
@@ -1449,7 +1449,7 @@ Please send all bug fixes and enhancements to
     (error "`ps-print' requires floating point support"))
 
 (let ((case-fold-search t))
-  (cond ((string-match "XEmacs" emacs-version))
+  (cond ((featurep 'xemacs))
         ((string-match "Lucid" emacs-version)
          (error "`ps-print' doesn't support Lucid"))
         ((string-match "Epoch" emacs-version)