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[sxemacs] / lisp / subr.el

;;; subr.el --- basic lisp subroutines for SXEmacs

;; Copyright (C) 1985, 86, 92, 94, 95, 99, 2000, 2001, 2002, 2003
;;   Free Software Foundation, Inc.
;; Copyright (C) 1995 Tinker Systems and INS Engineering Corp.
;; Copyright (C) 1995 Sun Microsystems.
;; Copyright (C) 2000, 2001, 2002, 2003 Ben Wing.

;; Maintainer: SXEmacs Development Team
;; Keywords: extensions, dumped, internal

;; This file is part of SXEmacs.

;; SXEmacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; SXEmacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with this program.  If not, see <http://www.gnu.org/licenses/>.

;;; Synched up with: FSF 19.34.  Some things synched up with later versions.

;;; Commentary:

;; This file is dumped with SXEmacs.

;; There's not a whole lot in common now with the FSF version,
;; be wary when applying differences.  I've left in a number of lines
;; of commentary just to give diff(1) something to synch itself with to
;; provide useful context diffs. -sb

;; BEGIN SYNCHED WITH FSF 21.2

;;; Code:
(defvar custom-declare-variable-list nil
  "Record `defcustom' calls made before `custom.el' is loaded to handle them.
Each element of this list holds the arguments to one call to `defcustom'.")

;; Use this, rather than defcustom, in subr.el and other files loaded
;; before custom.el.  See dumped-lisp.el.
(defun custom-declare-variable-early (&rest arguments)
  (setq custom-declare-variable-list
        (cons arguments custom-declare-variable-list)))

\f
(defun macro-declaration-function (macro decl)
  "Process a declaration found in a macro definition.
This is set as the value of the variable `macro-declaration-function'.
MACRO is the name of the macro being defined.
DECL is a list `(declare ...)' containing the declarations.
The return value of this function is not used."
  (dolist (d (cdr decl))
    (cond ((and (consp d) (eq (car d) 'indent))
           (put macro 'lisp-indent-function (cadr d)))
          ((and (consp d) (eq (car d) 'debug))
           (put macro 'edebug-form-spec (cadr d)))
          (t
           (message "Unknown declaration %s" d)))))

(setq macro-declaration-function 'macro-declaration-function)

\f
;;;; Lisp language features.

(defmacro lambda (&rest cdr)
  "Return a lambda expression.
A call of the form (lambda ARGS DOCSTRING INTERACTIVE BODY) is
self-quoting; the result of evaluating the lambda expression is the
expression itself.  The lambda expression may then be treated as a
function, i.e., stored as the function value of a symbol, passed to
funcall or mapcar, etc.

ARGS should take the same form as an argument list for a `defun'.
Optional DOCSTRING is a documentation string.
If present, it should describe how to call the function.  Docstrings are
rarely useful unless the lambda will be named, eg, using `fset'.
Optional INTERACTIVE should be a call to the function `interactive'.
BODY should be a list of lisp expressions.

The byte-compiler treats lambda expressions specially.  If the lambda
expression is syntactically a function to be called, it will be compiled
unless protected by `quote'.  Conversely, quoting a lambda expression with
`function' hints to the byte-compiler that it should compile the expression.
\(The byte-compiler may or may not actually compile it; for example it will
never compile lambdas nested in a data structure: `'(#'(lambda (x) x))').

The byte-compiler will warn about common problems such as the form
`(fset 'f '(lambda (x) x))' (the lambda cannot be byte-compiled; probably
the programmer intended `#'', although leaving the lambda unquoted will
normally suffice), but in general is it the programmer's responsibility to
quote lambda expressions appropriately."
  `(function (lambda ,@cdr)))

;; FSF 21.2 has various basic macros here.  We don't because they're either
;; in cl*.el (which we dump and hence is always available) or built-in.

;; More powerful versions in cl.el.
;(defmacro push (newelt listname)
;(defmacro pop (listname)

;; Built-in.
;(defmacro when (cond &rest body)
;(defmacro unless (cond &rest body)

;; More powerful versions in cl-macs.el.
;(defmacro dolist (spec &rest body)
;(defmacro dotimes (spec &rest body)

;; In cl.el.  Ours are defun, but cl arranges for them to be inlined anyway.
;(defsubst caar (x)
;(defsubst cadr (x)
;(defsubst cdar (x)
;(defsubst cddr (x)

;; Built-in.  Our `last' is more powerful in that it handles circularity.
;(defun last (x &optional n)
;(defun butlast (x &optional n)
;(defun nbutlast (x &optional n)

;; In cl-seq.el.
;(defun remove (elt seq)
;(defun remq (elt list)

(defmacro defun-when-void (&rest args)
  "Define a function, just like `defun', unless it's already defined.
Used for compatibility among different emacs variants."
  `(if (fboundp ',(car args))
       nil
     (defun ,@args)))

(defmacro define-function-when-void (&rest args)
  "Define a function, just like `define-function', unless it's already defined.
Used for compatibility among different emacs variants."
  `(if (fboundp ,(car args))
       nil
     (define-function ,@args)))

\f
(defun assoc-default (key alist &optional test default)
  "Find object KEY in a pseudo-alist ALIST.
ALIST is a list of conses or objects.  Each element (or the element's car,
if it is a cons) is compared with KEY by evaluating (TEST (car elt) KEY).
If that is non-nil, the element matches;
then `assoc-default' returns the element's cdr, if it is a cons,
or DEFAULT if the element is not a cons.

If no element matches, the value is nil.
If TEST is omitted or nil, `equal' is used."
  (let (found (tail alist) value)
    (while (and tail (not found))
      (let ((elt (car tail)))
        (when (funcall (or test 'equal) (if (consp elt) (car elt) elt) key)
          (setq found t value (if (consp elt) (cdr elt) default))))
      (setq tail (cdr tail)))
    value))

(defun assoc-ignore-case (key alist)
  "Like `assoc', but ignores differences in case and text representation.
KEY must be a string.  Upper-case and lower-case letters are treated as equal."
  (let (element)
    (while (and alist (not element))
      (if (string= (downcase key) (downcase (car (car alist))))
          (setq element (car alist)))
      (setq alist (cdr alist)))
    element))

(defun assoc-ignore-representation (key alist)
  "Like `assoc', but ignores differences in text representation.
KEY must be a string."
  (let (element)
    (while (and alist (not element))
      (if (string= key (car (car alist)))
          (setq element (car alist)))
      (setq alist (cdr alist)))
    element))

(defun member-ignore-case (elt list)
  "Like `member', but ignores differences in case and text representation.
ELT must be a string.  Upper-case and lower-case letters are treated as equal."
  (while (and list (not (string= (downcase elt) (downcase (car list)))))
    (setq list (cdr list)))
  list)

\f
;;;; Keymap support.
;; XEmacs: removed to keymap.el

;;;; The global keymap tree.

;;; global-map, esc-map, and ctl-x-map have their values set up in
;;; keymap.c; we just give them docstrings here.

;;;; Event manipulation functions.

;; XEmacs: This stuff is done in C Code.

;;;; Obsolescent names for functions generally appear elsewhere, in
;;;; obsolete.el or in the files they are related do.  Many very old
;;;; obsolete stuff has been removed entirely (e.g. anything with `dot' in
;;;; place of `point').

; alternate names (not obsolete)
(if (not (fboundp 'mod)) (define-function 'mod '%))
(define-function 'move-marker 'set-marker)
(define-function 'beep 'ding)           ; preserve lingual purity
(define-function 'indent-to-column 'indent-to)
(define-function 'backward-delete-char 'delete-backward-char)
(define-function 'search-forward-regexp (symbol-function 're-search-forward))
(define-function 'search-backward-regexp (symbol-function 're-search-backward))
(define-function 'remove-directory 'delete-directory)
(define-function 'set-match-data 'store-match-data)
(define-function 'send-string-to-terminal 'external-debugging-output)

;; XEmacs:
(defun local-variable-if-set-p (sym buffer)
  "Return t if SYM would be local to BUFFER after it is set.
A nil value for BUFFER is *not* the same as (current-buffer), but
can be used to determine whether `make-variable-buffer-local' has been
called on SYM."
  (local-variable-p sym buffer t))

\f
;;;; Hook manipulation functions.

;; (defconst run-hooks 'run-hooks ...)

(defun make-local-hook (hook)
  "Make the hook HOOK local to the current buffer.
The return value is HOOK.

You never need to call this function now that `add-hook' does it for you
if its LOCAL argument is non-nil.

When a hook is local, its local and global values
work in concert: running the hook actually runs all the hook
functions listed in *either* the local value *or* the global value
of the hook variable.

This function works by making `t' a member of the buffer-local value,
which acts as a flag to run the hook functions in the default value as
well.  This works for all normal hooks, but does not work for most
non-normal hooks yet.  We will be changing the callers of non-normal
hooks so that they can handle localness; this has to be done one by
one.

This function does nothing if HOOK is already local in the current
buffer.

Do not use `make-local-variable' to make a hook variable buffer-local."
  (if (local-variable-p hook (current-buffer)) ; XEmacs
      nil
    (or (boundp hook) (set hook nil))
    (make-local-variable hook)
    (set hook (list t)))
  hook)

(defun add-hook (hook function &optional append local)
  "Add to the value of HOOK the function FUNCTION.
FUNCTION is not added if already present.
FUNCTION is added (if necessary) at the beginning of the hook list
unless the optional argument APPEND is non-nil, in which case
FUNCTION is added at the end.

The optional fourth argument, LOCAL, if non-nil, says to modify
the hook's buffer-local value rather than its default value.
This makes the hook buffer-local if needed.
To make a hook variable buffer-local, always use
`make-local-hook', not `make-local-variable'.

HOOK should be a symbol, and FUNCTION may be any valid function.  If
HOOK is void, it is first set to nil.  If HOOK's value is a single
function, it is changed to a list of functions.

You can remove this hook yourself using `remove-hook'.

See also `add-one-shot-hook'."
  (or (boundp hook) (set hook nil))
  (or (default-boundp hook) (set-default hook nil))
  (if local (unless (local-variable-if-set-p hook (current-buffer)) ; XEmacs
              (make-local-hook hook))
    ;; Detect the case where make-local-variable was used on a hook
    ;; and do what we used to do.
    (unless (and (consp (symbol-value hook)) (memq t (symbol-value hook)))
      (setq local t)))
  (let ((hook-value (if local (symbol-value hook) (default-value hook))))
    ;; If the hook value is a single function, turn it into a list.
    (when (or (not (listp hook-value)) (eq (car hook-value) 'lambda))
      (setq hook-value (list hook-value)))
    ;; Do the actual addition if necessary
    (unless (member function hook-value)
      (setq hook-value
            (if append
                (append hook-value (list function))
              (cons function hook-value))))
    ;; Set the actual variable
    (if local (set hook hook-value) (set-default hook hook-value))))

(defun remove-hook (hook function &optional local)
  "Remove from the value of HOOK the function FUNCTION.
HOOK should be a symbol, and FUNCTION may be any valid function.  If
FUNCTION isn't the value of HOOK, or, if FUNCTION doesn't appear in the
list of hooks to run in HOOK, then nothing is done.  See `add-hook'.

The optional third argument, LOCAL, if non-nil, says to modify
the hook's buffer-local value rather than its default value.
This makes the hook buffer-local if needed.
To make a hook variable buffer-local, always use
`make-local-hook', not `make-local-variable'."
  (or (boundp hook) (set hook nil))
  (or (default-boundp hook) (set-default hook nil))
  (if local (unless (local-variable-if-set-p hook (current-buffer)) ; XEmacs
              (make-local-hook hook))
    ;; Detect the case where make-local-variable was used on a hook
    ;; and do what we used to do.
    (unless (and (consp (symbol-value hook)) (memq t (symbol-value hook)))
      (setq local t)))
  (let ((hook-value (if local (symbol-value hook) (default-value hook))))
    ;; Remove the function, for both the list and the non-list cases.
    ;; XEmacs: add hook-test, for handling one-shot hooks.
    (flet ((hook-test
             (fn hel)
             (or (equal fn hel)
                 (and (symbolp hel)
                      (equal fn
                             (get hel 'one-shot-hook-fun))))))
      (if (or (not (listp hook-value)) (eq (car hook-value) 'lambda))
          (if (equal hook-value function) (setq hook-value nil))
        (setq hook-value (delete* function (copy-sequence hook-value)
                                  :test 'hook-test)))
      ;; If the function is on the global hook, we need to shadow it locally
      ;;(when (and local (member* function (default-value hook)
      ;;                          :test 'hook-test)
      ;;               (not (member* (cons 'not function) hook-value
      ;;                             :test 'hook-test)))
      ;;  (push (cons 'not function) hook-value))
      ;; Set the actual variable
      (if local (set hook hook-value) (set-default hook hook-value)))))

;; XEmacs addition
;; #### we need a coherent scheme for indicating compatibility info,
;; so that it can be programmatically retrieved.
(defun add-local-hook (hook function &optional append)
  "Add to the local value of HOOK the function FUNCTION.
You don't need this any more.  It's equivalent to specifying the LOCAL
argument to `add-hook'."
  (add-hook hook function append t))

;; XEmacs addition
(defun remove-local-hook (hook function)
  "Remove from the local value of HOOK the function FUNCTION.
You don't need this any more.  It's equivalent to specifying the LOCAL
argument to `remove-hook'."
  (remove-hook hook function t))

(defun add-one-shot-hook (hook function &optional append local)
  "Add to the value of HOOK the one-shot function FUNCTION.
FUNCTION will automatically be removed from the hook the first time
after it runs (whether to completion or to an error).
FUNCTION is not added if already present.
FUNCTION is added (if necessary) at the beginning of the hook list
unless the optional argument APPEND is non-nil, in which case
FUNCTION is added at the end.

HOOK should be a symbol, and FUNCTION may be any valid function.  If
HOOK is void, it is first set to nil.  If HOOK's value is a single
function, it is changed to a list of functions.

You can remove this hook yourself using `remove-hook'.

See also `add-hook'."
  (let ((sym (gensym)))
    (fset sym `(lambda (&rest args)
                 (unwind-protect
                     (apply ',function args)
                   (remove-hook ',hook ',sym ',local))))
    (put sym 'one-shot-hook-fun function)
    (add-hook hook sym append local)))

(defun add-local-one-shot-hook (hook function &optional append)
  "Add to the local value of HOOK the one-shot function FUNCTION.
You don't need this any more.  It's equivalent to specifying the LOCAL
argument to `add-one-shot-hook'."
  (add-one-shot-hook hook function append t))


(defun add-hook-list (function  hook-list &optional append &optional local)
  "FUNCTION is not added if already present.
FUNCTION is added (if necessary) at the beginning of the hook list
unless the optional argument APPEND is non-nil, in which case
FUNCTION is added at the end.

The optional fourth argument, LOCAL, if non-nil, says to modify
the hook's buffer-local value rather than its default value.
This makes the hook buffer-local if needed.
To make a hook variable buffer-local, always use
`make-local-hook', not `make-local-variable'.

HOOK-LIST should be a list of symbols, and FUNCTION may be any valid
function.  If HOOK is void, it is first set to nil.  If HOOK's value
is a single function, it is changed to a list of functions.

You can remove this hook yourself using `remove-hook-list'.

See also `add-hook`, `remove-hook` and `add-one-shot-hook'."
  (mapc (lambda (hook)
          (add-hook hook function append local))
        hook-list))

(defun remove-hook-list (function  hook-list &optional local)
  "Remove from the value of all members of HOOK-LIST the function FUNCTION.
HOOK-LIST should be a list of symbols, and FUNCTION may be any valid
function.  If FUNCTION isn't the value of the member of HOOK-LIST, or,
if FUNCTION doesn't appear in the list of hooks to run in HOOK, then
nothing is done.  See `add-hook-list` and `add-hook'.

The optional third argument, LOCAL, if non-nil, says to modify
the hook's buffer-local value rather than its default value.
This makes the hook buffer-local if needed.
To make a hook variable buffer-local, always use
`make-local-hook', not `make-local-variable'."
  (mapc (lambda (hook)
          (remove-hook hook function local))
        hook-list))


(defun add-to-list (list-var element &optional append)
  "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet.
The test for presence of ELEMENT is done with `equal'.
If ELEMENT is added, it is added at the beginning of the list,
unless the optional argument APPEND is non-nil, in which case
ELEMENT is added at the end.

If you want to use `add-to-list' on a variable that is not defined
until a certain package is loaded, you should put the call to `add-to-list'
into a hook function that will be run only after loading the package.
`eval-after-load' provides one way to do this.  In some cases
other hooks, such as major mode hooks, can do the job."
  (if (member element (symbol-value list-var))
      (symbol-value list-var)
    (set list-var
         (if append
             (append (symbol-value list-var) (list element))
           (cons element (symbol-value list-var))))))

;; END SYNCHED WITH FSF 21.2

;; XEmacs additions

(defun add-to-list* (list-var element &optional append)
    "Add to the value of LIST-VAR the element ELEMENT if it isn't there yet.
The test for presence of ELEMENT is done with `equal'.
If ELEMENT is added, it is added at the beginning of the list,
unless the optional argument APPEND is non-nil, in which case
ELEMENT is added at the end.

If LIST-VAR is not defined as a variable yet, it will set it to a list
of just the element.

If you want to use `add-to-list*' on a variable that is not defined
until a certain package is loaded, you should put the call to `add-to-list*'
into a hook function that will be run only after loading the package.
`eval-after-load' provides one way to do this.  In some cases
other hooks, such as major mode hooks, can do the job."
    (if (boundp list-var)
        (add-to-list list-var element append)
      (set list-var (list element))))

;; called by Fkill_buffer()
(defvar kill-buffer-hook nil
  "Function or functions to be called when a buffer is killed.
The value of this variable may be buffer-local.
The buffer about to be killed is current when this hook is run.")

;; in C in FSFmacs
(defvar kill-emacs-hook nil
  "Function or functions to be called when `kill-emacs' is called,
just before emacs is actually killed.")

;; not obsolete.
;; #### These are a bad idea, because the CL RPLACA and RPLACD
;; return the cons cell, not the new CAR/CDR.         -hniksic
;; The proper definition would be:
;; (defun rplaca (conscell newcar)
;;   (setcar conscell newcar)
;;   conscell)
;; ...and analogously for RPLACD.
(define-function 'rplaca 'setcar)
(define-function 'rplacd 'setcdr)

(defun copy-symbol (symbol &optional copy-properties)
  "Return a new uninterned symbol with the same name as SYMBOL.
If COPY-PROPERTIES is non-nil, the new symbol will have a copy of
SYMBOL's value, function, and property lists."
  (let ((new (make-symbol (symbol-name symbol))))
    (when copy-properties
      ;; This will not copy SYMBOL's chain of forwarding objects, but
      ;; I think that's OK.  Callers should not expect such magic to
      ;; keep working in the copy in the first place.
      (and (boundp symbol)
           (set new (symbol-value symbol)))
      (and (fboundp symbol)
           (fset new (symbol-function symbol)))
      (setplist new (copy-list (symbol-plist symbol))))
    new))

(defun set-symbol-value-in-buffer (sym val buffer)
  "Set the value of SYM to VAL in BUFFER.  Useful with buffer-local variables.
If SYM has a buffer-local value in BUFFER, or will have one if set, this
function allows you to set the local value.

NOTE: At some point, this will be moved into C and will be very fast."
  (with-current-buffer buffer
    (set sym val)))

\f
;; BEGIN SYNCHED WITH FSF 21.2

;; #### #### #### AAaargh!  Must be in C, because it is used insanely
;; early in the bootstrap process.
;(defun split-path (path)
;  "Explode a search path into a list of strings.
;The path components are separated with the characters specified
;with `path-separator'."
;  (while (or (not stringp path-separator)
;            (/= (length path-separator) 1))
;    (setq path-separator (signal 'error (list "\
;`path-separator' should be set to a single-character string"
;                                             path-separator))))
;  (split-string-by-char path (aref separator 0)))

(defmacro with-current-buffer (buffer &rest body)
  "Temporarily make BUFFER the current buffer and execute the forms in BODY.
The value returned is the value of the last form in BODY.
See also `with-temp-buffer'."
  `(save-current-buffer
    (set-buffer ,buffer)
    ,@body))

(defmacro with-temp-file (filename &rest forms)
  "Create a new buffer, evaluate FORMS there, and write the buffer to FILENAME.
The value of the last form in FORMS is returned, like `progn'.
See also `with-temp-buffer'."
  (let ((temp-file (make-symbol "temp-file"))
        (temp-buffer (make-symbol "temp-buffer")))
    `(let ((,temp-file ,filename)
           (,temp-buffer
            (get-buffer-create (generate-new-buffer-name " *temp file*"))))
       (unwind-protect
           (prog1
               (with-current-buffer ,temp-buffer
                 ,@forms)
             (with-current-buffer ,temp-buffer
               (widen)
               (write-region (point-min) (point-max) ,temp-file nil 0)))
         (and (buffer-name ,temp-buffer)
              (kill-buffer ,temp-buffer))))))

;; FSF compatibility
(defmacro with-temp-message (message &rest body)
  "Display MESSAGE temporarily while BODY is evaluated.
The original message is restored to the echo area after BODY has finished.
The value returned is the value of the last form in BODY.
If MESSAGE is nil, the echo area and message log buffer are unchanged.
Use a MESSAGE of \"\" to temporarily clear the echo area.

Note that this function exists for FSF compatibility purposes.  A better way
under XEmacs is to give the message a particular label (see `display-message');
then, the old message is automatically restored when you clear your message
with `clear-message'."
;; FSF additional doc string from 21.2:
;; MESSAGE is written to the message log buffer if `message-log-max' is non-nil.
  (let ((current-message (make-symbol "current-message"))
        (temp-message (make-symbol "with-temp-message")))
    `(let ((,temp-message ,message)
           (,current-message))
       (unwind-protect
           (progn
             (when ,temp-message
               (setq ,current-message (current-message))
               (message "%s" ,temp-message))
             ,@body)
         (and ,temp-message ,current-message
              (message "%s" ,current-message))))))

(defmacro with-temp-buffer (&rest forms)
  "Create a temporary buffer, and evaluate FORMS there like `progn'.
See also `with-temp-file' and `with-output-to-string'."
  (let ((temp-buffer (make-symbol "temp-buffer")))
    `(let ((,temp-buffer
            (get-buffer-create (generate-new-buffer-name " *temp*"))))
       (unwind-protect
           (with-current-buffer ,temp-buffer
             ,@forms)
         (and (buffer-name ,temp-buffer)
              (kill-buffer ,temp-buffer))))))

(defmacro with-output-to-string (&rest body)
  "Execute BODY, return the text it sent to `standard-output', as a string."
  `(let ((standard-output
          (get-buffer-create (generate-new-buffer-name " *string-output*"))))
     (let ((standard-output standard-output))
       ,@body)
     (with-current-buffer standard-output
       (prog1
           (buffer-string)
         (kill-buffer nil)))))

(defmacro with-local-quit (&rest body)
  "Execute BODY with `inhibit-quit' temporarily bound to nil."
  `(condition-case nil
       (let ((inhibit-quit nil))
         ,@body)
     (quit (setq quit-flag t))))

;; FSF 21.3.

; (defmacro combine-after-change-calls (&rest body)
;   "Execute BODY, but don't call the after-change functions till the end.
; If BODY makes changes in the buffer, they are recorded
; and the functions on `after-change-functions' are called several times
; when BODY is finished.
; The return value is the value of the last form in BODY.

; If `before-change-functions' is non-nil, then calls to the after-change
; functions can't be deferred, so in that case this macro has no effect.

; Do not alter `after-change-functions' or `before-change-functions'
; in BODY."
;   (declare (indent 0) (debug t))
;   `(unwind-protect
;        (let ((combine-after-change-calls t))
;        . ,body)
;      (combine-after-change-execute)))


(defvar delay-mode-hooks nil
  "If non-nil, `run-mode-hooks' should delay running the hooks.")
(defvar delayed-mode-hooks nil
  "List of delayed mode hooks waiting to be run.")
(make-variable-buffer-local 'delayed-mode-hooks)
(put 'delay-mode-hooks 'permanent-local t)

(defun run-mode-hooks (&rest hooks)
  "Run mode hooks `delayed-mode-hooks' and HOOKS, or delay HOOKS.
Execution is delayed if `delay-mode-hooks' is non-nil.
Major mode functions should use this."
  (if delay-mode-hooks
      ;; Delaying case.
      (dolist (hook hooks)
        (push hook delayed-mode-hooks))
    ;; Normal case, just run the hook as before plus any delayed hooks.
    (setq hooks (nconc (nreverse delayed-mode-hooks) hooks))
    (setq delayed-mode-hooks nil)
    (apply 'run-hooks hooks)))

(defmacro delay-mode-hooks (&rest body)
  "Execute BODY, but delay any `run-mode-hooks'.
Only affects hooks run in the current buffer."
  `(progn
     (make-local-variable 'delay-mode-hooks)
     (let ((delay-mode-hooks t))
       ,@body)))

(defmacro with-syntax-table (table &rest body)
  "Evaluate BODY with syntax table of current buffer set to a copy of TABLE.
The syntax table of the current buffer is saved, BODY is evaluated, and the
saved table is restored, even in case of an abnormal exit.
Value is what BODY returns."
  (let ((old-table (make-symbol "table"))
        (old-buffer (make-symbol "buffer")))
    `(let ((,old-table (syntax-table))
           (,old-buffer (current-buffer)))
       (unwind-protect
           (progn
             (set-syntax-table (copy-syntax-table ,table))
             ,@body)
         (save-current-buffer
           (set-buffer ,old-buffer)
           (set-syntax-table ,old-table))))))

(put 'with-syntax-table 'lisp-indent-function 1)
(put 'with-syntax-table 'edebug-form-spec '(form body))


;; Moved from mule-coding.el.
(defmacro with-string-as-buffer-contents (str &rest body)
  "With the contents of the current buffer being STR, run BODY.
Returns the new contents of the buffer, as modified by BODY.
The original current buffer is restored afterwards."
  `(with-temp-buffer
     (insert ,str)
     ,@body
     (buffer-string)))

\f
(defmacro save-match-data (&rest body)
  "Execute BODY forms, restoring the global value of the match data."
  (let ((original (make-symbol "match-data")))
    (list 'let (list (list original '(match-data)))
          (list 'unwind-protect
                (cons 'progn body)
                (list 'store-match-data original)))))


(defun match-string (num &optional string)
  "Return string of text matched by last search.
NUM specifies which parenthesized expression in the last regexp.
 Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
Zero means the entire text matched by the whole regexp or whole string.
STRING should be given if the last search was by `string-match' on STRING."
  (if (match-beginning num)
      (if string
          (substring string (match-beginning num) (match-end num))
        (buffer-substring (match-beginning num) (match-end num)))))

(defun match-string-no-properties (num &optional string)
  "Return string of text matched by last search, without text properties.
NUM specifies which parenthesized expression in the last regexp.
 Value is nil if NUMth pair didn't match, or there were less than NUM pairs.
Zero means the entire text matched by the whole regexp or whole string.
STRING should be given if the last search was by `string-match' on STRING."
  (if (match-beginning num)
      (if string
          (let ((result
                 (substring string (match-beginning num) (match-end num))))
            (set-text-properties 0 (length result) nil result)
            result)
        (buffer-substring-no-properties (match-beginning num)
                                        (match-end num)))))

(defconst split-string-default-separators "[ \f\t\n\r\v]+"
  "The default value of separators for `split-string'.

A regexp matching strings of whitespace.  May be locale-dependent
\(as yet unimplemented).  Should not match non-breaking spaces.

Warning: binding this to a different value and using it as default is
likely to have undesired semantics.")

;; specification for `split-string' agreed with rms 2003-04-23
;; xemacs design <87vfx5vor0.fsf@tleepslib.sk.tsukuba.ac.jp>

;; The specification says that if both SEPARATORS and OMIT-NULLS are
;; defaulted, OMIT-NULLS should be treated as t.  Simplifying the logical
;; expression leads to the equivalent implementation that if SEPARATORS
;; is defaulted, OMIT-NULLS is treated as t.

(defun split-string (string &optional separators omit-nulls)
  "Splits STRING into substrings bounded by matches for SEPARATORS.

The beginning and end of STRING, and each match for SEPARATORS, are
splitting points.  The substrings matching SEPARATORS are removed, and
the substrings between the splitting points are collected as a list,
which is returned.

If SEPARATORS is non-`nil', it should be a regular expression matching text
which separates, but is not part of, the substrings.  If `nil' it defaults to
`split-string-default-separators', normally \"[ \\f\\t\\n\\r\\v]+\", and
OMIT-NULLS is forced to `t'.

If OMIT-NULLS is `t', zero-length substrings are omitted from the list \(so
that for the default value of SEPARATORS leading and trailing whitespace
are effectively trimmed).  If `nil', all zero-length substrings are retained,
which correctly parses CSV format, for example.

Note that the effect of `(split-string STRING)' is the same as
`(split-string STRING split-string-default-separators t)').  In the rare
case that you wish to retain zero-length substrings when splitting on
whitespace, use `(split-string STRING split-string-default-separators nil)'.

Modifies the match data when successful; use `save-match-data' if necessary."