;;; wid-edit.el --- Functions for creating and using widgets -*-byte-compile-dynamic: t;-*-
;;
-;; Copyright (C) 1996, 1997, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+;; Copyright (C) 1996,97,1999,2000,01,02,2003, 2004 Free Software Foundation, Inc.
;;
;; Author: Per Abrahamsen <abraham@dina.kvl.dk>
;; Maintainer: FSF
(setq help-echo 'widget-mouse-help))
(overlay-put overlay 'button widget)
(overlay-put overlay 'keymap (widget-get widget :keymap))
+ (overlay-put overlay 'evaporate t)
;; We want to avoid the face with image buttons.
(unless (widget-get widget :suppress-face)
- (overlay-put overlay 'face (widget-apply widget :button-face-get))
- (overlay-put overlay 'mouse-face widget-mouse-face))
+ (overlay-put overlay 'face (widget-apply widget :button-face-get)))
+ (overlay-put overlay 'pointer 'hand)
(overlay-put overlay 'help-echo help-echo)))
(defun widget-mouse-help (window overlay point)
"Specify sample for WIDGET between FROM and TO."
(let ((overlay (make-overlay from to nil t nil)))
(overlay-put overlay 'face (widget-apply widget :sample-face-get))
+ (overlay-put overlay 'evaporate t)
(widget-put widget :sample-overlay overlay)))
(defun widget-specify-doc (widget from to)
(let ((overlay (make-overlay from to nil t nil)))
(overlay-put overlay 'widget-doc widget)
(overlay-put overlay 'face widget-documentation-face)
+ (overlay-put overlay 'evaporate t)
(widget-put widget :doc-overlay overlay)))
(defmacro widget-specify-insert (&rest form)
"Execute FORM without inheriting any text properties."
`(save-restriction
(let ((inhibit-read-only t)
- (inhibit-modification-hooks t)
- result)
- (insert "<>")
- (narrow-to-region (- (point) 2) (point))
- (goto-char (1+ (point-min)))
- (setq result (progn ,@form))
- (delete-region (point-min) (1+ (point-min)))
- (delete-region (1- (point-max)) (point-max))
- (goto-char (point-max))
- result)))
+ (inhibit-modification-hooks t))
+ (narrow-to-region (point) (point))
+ (prog1 (progn ,@form)
+ (goto-char (point-max))))))
(defface widget-inactive-face '((((class grayscale color)
(background dark))
respectively."
(let ((cur (point-min))
(widget nil)
- (parent nil)
(overlays (if buffer
(with-current-buffer buffer (overlay-lists))
(overlay-lists))))
(or (bobp) (> arg 0) (backward-char))
(let ((wrapped 0)
(number arg)
- (old (widget-tabable-at))
- new)
+ (old (widget-tabable-at)))
;; Forward.
(while (> arg 0)
(cond ((eobp)
field)))
(defun widget-field-buffer (widget)
- "Return the start of WIDGET's editing field."
+ "Return the buffer of WIDGET's editing field."
(let ((overlay (widget-get widget :field-overlay)))
(cond ((overlayp overlay)
(overlay-buffer overlay))
found (widget-apply child :validate)))
found))
+(defun widget-child-value-get (widget)
+ "Get the value of the first member of :children in WIDGET."
+ (widget-value (car (widget-get widget :children))))
+
+(defun widget-child-value-inline (widget)
+ "Get the inline value of the first member of :children in WIDGET."
+ (widget-apply (car (widget-get widget :children)) :value-inline))
+
+(defun widget-child-validate (widget)
+ "The result of validating the first member of :children in WIDGET."
+ (widget-apply (car (widget-get widget :children)) :validate))
+
+(defun widget-type-value-create (widget)
+ "Convert and instantiate the value of the :type attribute of WIDGET.
+Store the newly created widget in the :children attribute.
+
+The value of the :type attribute should be an unconverted widget type."
+ (let ((value (widget-get widget :value))
+ (type (widget-get widget :type)))
+ (widget-put widget :children
+ (list (widget-create-child-value widget
+ (widget-convert type)
+ value)))))
+
+(defun widget-type-default-get (widget)
+ "Get default value from the :type attribute of WIDGET.
+
+The value of the :type attribute should be an unconverted widget type."
+ (widget-default-get (widget-convert (widget-get widget :type))))
+
+(defun widget-type-match (widget value)
+ "Non-nil if the :type value of WIDGET matches VALUE.
+
+The value of the :type attribute should be an unconverted widget type."
+ (widget-apply (widget-convert (widget-get widget :type)) :match value))
+
(defun widget-types-copy (widget)
"Copy :args as widget types in WIDGET."
(widget-put widget :args (mapcar 'widget-copy (widget-get widget :args)))
:copy 'identity
:value-set 'widget-default-value-set
:value-inline 'widget-default-value-inline
+ :value-delete 'ignore
:default-get 'widget-default-default-get
:menu-tag-get 'widget-default-menu-tag-get
:validate #'ignore
(inhibit-modification-hooks t)
(inhibit-read-only t))
(widget-apply widget :value-delete)
+ (widget-children-value-delete widget)
(when inactive-overlay
(delete-overlay inactive-overlay))
(when button-overlay
:tag "choice"
:void '(item :format "invalid (%t)\n")
:value-create 'widget-choice-value-create
- :value-delete 'widget-children-value-delete
- :value-get 'widget-choice-value-get
- :value-inline 'widget-choice-value-inline
+ :value-get 'widget-child-value-get
+ :value-inline 'widget-child-value-inline
:default-get 'widget-choice-default-get
:mouse-down-action 'widget-choice-mouse-down-action
:action 'widget-choice-action
widget void :value value)))
(widget-put widget :choice void))))))
-(defun widget-choice-value-get (widget)
- ;; Get value of the child widget.
- (widget-value (car (widget-get widget :children))))
-
-(defun widget-choice-value-inline (widget)
- ;; Get value of the child widget.
- (widget-apply (car (widget-get widget :children)) :value-inline))
-
(defun widget-choice-default-get (widget)
;; Get default for the first choice.
(widget-default-get (car (widget-get widget :args))))
:entry-format "%b %v"
:greedy nil
:value-create 'widget-checklist-value-create
- :value-delete 'widget-children-value-delete
:value-get 'widget-checklist-value-get
:validate 'widget-checklist-validate
:match 'widget-checklist-match
:format "%v"
:entry-format "%b %v"
:value-create 'widget-radio-value-create
- :value-delete 'widget-children-value-delete
:value-get 'widget-radio-value-get
:value-inline 'widget-radio-value-inline
:value-set 'widget-radio-value-set
:format-handler 'widget-editable-list-format-handler
:entry-format "%i %d %v"
:value-create 'widget-editable-list-value-create
- :value-delete 'widget-children-value-delete
:value-get 'widget-editable-list-value-get
:validate 'widget-children-validate
:match 'widget-editable-list-match
(defun widget-editable-list-format-handler (widget escape)
;; We recognize the insert button.
-;;; (let ((widget-push-button-gui widget-editable-list-gui))
+ ;; (let ((widget-push-button-gui widget-editable-list-gui))
(cond ((eq escape ?i)
(and (widget-get widget :indent)
(insert-char ?\ (widget-get widget :indent)))
(widget-get widget :append-button-args)))
(t
(widget-default-format-handler widget escape)))
-;;; )
+ ;; )
)
(defun widget-editable-list-value-create (widget)
(defun widget-editable-list-entry-create (widget value conv)
;; Create a new entry to the list.
(let ((type (nth 0 (widget-get widget :args)))
-;;; (widget-push-button-gui widget-editable-list-gui)
+ ;; (widget-push-button-gui widget-editable-list-gui)
child delete insert)
(widget-specify-insert
(save-excursion
widget type (widget-default-get type)))))
(t
(error "Unknown escape `%c'" escape)))))
- (widget-put widget
- :buttons (cons delete
- (cons insert
- (widget-get widget :buttons))))
+ (let ((buttons (widget-get widget :buttons)))
+ (if insert (push insert buttons))
+ (if delete (push delete buttons))
+ (widget-put widget :buttons buttons))
(let ((entry-from (point-min-marker))
(entry-to (point-max-marker)))
(set-marker-insertion-type entry-from t)
(set-marker-insertion-type entry-to nil)
(widget-put child :entry-from entry-from)
(widget-put child :entry-to entry-to)))
- (widget-put insert :widget child)
- (widget-put delete :widget child)
+ (if insert (widget-put insert :widget child))
+ (if delete (widget-put delete :widget child))
child))
;;; The `group' Widget.
:copy 'widget-types-copy
:format "%v"
:value-create 'widget-group-value-create
- :value-delete 'widget-children-value-delete
:value-get 'widget-editable-list-value-get
:default-get 'widget-group-default-get
:validate 'widget-children-validate
"A documentation string."
:format "%v"
:action 'widget-documentation-string-action
- :value-delete 'widget-children-value-delete
:value-create 'widget-documentation-string-value-create)
(defun widget-documentation-string-value-create (widget)
(setq err "Empty sexp -- use `nil'?")
(unless (widget-apply widget :match (read (current-buffer)))
(setq err (widget-get widget :type-error))))
+ ;; Allow whitespace after expression.
+ (skip-syntax-forward "\\s-")
(if (and (not (eobp))
(not err))
(setq err (format "Junk at end of expression: %s"
:value-to-internal (lambda (widget value)
(list (car value) (cdr value)))
:value-to-external (lambda (widget value)
- (cons (nth 0 value) (nth 1 value))))
+ (apply 'cons value)))
(defun widget-cons-match (widget value)
(and (consp value)
(widget-group-match widget
(widget-apply widget :value-to-internal value))))
\f
+;;; The `lazy' Widget.
+;;
+;; Recursive datatypes.
+
+(define-widget 'lazy 'default
+ "Base widget for recursive datastructures.
+
+The `lazy' widget will, when instantiated, contain a single inferior
+widget, of the widget type specified by the :type parameter. The
+value of the `lazy' widget is the same as the value of the inferior
+widget. When deriving a new widget from the 'lazy' widget, the :type
+parameter is allowed to refer to the widget currently being defined,
+thus allowing recursive datastructures to be described.
+
+The :type parameter takes the same arguments as the defcustom
+parameter with the same name.
+
+Most composite widgets, i.e. widgets containing other widgets, does
+not allow recursion. That is, when you define a new widget type, none
+of the inferior widgets may be of the same type you are currently
+defining.
+
+In Lisp, however, it is custom to define datastructures in terms of
+themselves. A list, for example, is defined as either nil, or a cons
+cell whose cdr itself is a list. The obvious way to translate this
+into a widget type would be
+
+ (define-widget 'my-list 'choice
+ \"A list of sexps.\"
+ :tag \"Sexp list\"
+ :args '((const nil) (cons :value (nil) sexp my-list)))
+
+Here we attempt to define my-list as a choice of either the constant
+nil, or a cons-cell containing a sexp and my-lisp. This will not work
+because the `choice' widget does not allow recursion.
+
+Using the `lazy' widget you can overcome this problem, as in this
+example:
+
+ (define-widget 'sexp-list 'lazy
+ \"A list of sexps.\"
+ :tag \"Sexp list\"
+ :type '(choice (const nil) (cons :value (nil) sexp sexp-list)))"
+ :format "%{%t%}: %v"
+ ;; We don't convert :type because we want to allow recursive
+ ;; datastructures. This is slow, so we should not create speed
+ ;; critical widgets by deriving from this.
+ :convert-widget 'widget-value-convert-widget
+ :value-create 'widget-type-value-create
+ :value-get 'widget-child-value-get
+ :value-inline 'widget-child-value-inline
+ :default-get 'widget-type-default-get
+ :match 'widget-type-match
+ :validate 'widget-child-validate)
+
+\f
;;; The `plist' Widget.
;;
;; Property lists.
(prompt (concat tag ": "))
(value (widget-value widget))
(start (widget-field-start widget))
- (pos (cond ((< (point) start)
- 0)
- ((> (point) (+ start (length value)))
- (length value))
- (t
- (- (point) start))))
(answer (facemenu-read-color prompt)))
(unless (zerop (length answer))
(widget-value-set widget answer)
(help-echo (and widget (widget-get widget :help-echo))))
(if (functionp help-echo)
(setq help-echo (funcall help-echo widget)))
- (if (stringp help-echo)
- (message "%s" help-echo))))
+ (if help-echo (message "%s" (eval help-echo)))))
;;; The End:
(provide 'wid-edit)
+;;; arch-tag: a076e75e-18a1-4b46-8be5-3f317bcbc707
;;; wid-edit.el ends here