diff options
Diffstat (limited to 'lisp/emacs-lisp/gv.el')
| -rw-r--r-- | lisp/emacs-lisp/gv.el | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/lisp/emacs-lisp/gv.el b/lisp/emacs-lisp/gv.el index cf090e5e758..66241897536 100644 --- a/lisp/emacs-lisp/gv.el +++ b/lisp/emacs-lisp/gv.el @@ -1,6 +1,6 @@ ;;; gv.el --- generalized variables -*- lexical-binding: t -*- -;; Copyright (C) 2012-2013 Free Software Foundation, Inc. +;; Copyright (C) 2012-2014 Free Software Foundation, Inc. ;; Author: Stefan Monnier <monnier@iro.umontreal.ca> ;; Keywords: extensions @@ -102,7 +102,9 @@ DO must return an Elisp expression." ;; Follow aliases. (setq me (cons (symbol-function head) (cdr place)))) (if (eq me place) - (error "%S is not a valid place expression" place) + (if (and (symbolp head) (get head 'setf-method)) + (error "Incompatible place needs recompilation: %S" head) + (error "%S is not a valid place expression" place)) (gv-get me do))))))) ;;;###autoload @@ -155,11 +157,13 @@ arguments as NAME. DO is a function as defined in `gv-get'." (_ (message "Unknown %s declaration %S" symbol handler) nil)))) ;;;###autoload -(push `(gv-expander ,(apply-partially #'gv--defun-declaration 'gv-expander)) - defun-declarations-alist) +(or (assq 'gv-expander defun-declarations-alist) + (push `(gv-expander ,(apply-partially #'gv--defun-declaration 'gv-expander)) + defun-declarations-alist)) ;;;###autoload -(push `(gv-setter ,(apply-partially #'gv--defun-declaration 'gv-setter)) - defun-declarations-alist) +(or (assq 'gv-setter defun-declarations-alist) + (push `(gv-setter ,(apply-partially #'gv--defun-declaration 'gv-setter)) + defun-declarations-alist)) ;; (defmacro gv-define-expand (name expander) ;; "Use EXPANDER to handle NAME as a generalized var. @@ -217,13 +221,15 @@ instead the assignment is turned into something equivalent to temp) so as to preserve the semantics of `setf'." (declare (debug (sexp (&or symbolp lambda-expr) &optional sexp))) + (when (eq 'lambda (car-safe setter)) + (message "Use `gv-define-setter' or name %s's setter function" name)) `(gv-define-setter ,name (val &rest args) ,(if fix-return `(macroexp-let2 nil v val `(progn - (,',setter ,@(append args (list v))) + (,',setter ,@args ,v) ,v)) - `(cons ',setter (append args (list val)))))) + ``(,',setter ,@args ,val)))) ;;; Typical operations on generalized variables. @@ -342,6 +348,10 @@ The return value is the last VAL in the list. (gv-define-simple-setter window-point set-window-point) (gv-define-simple-setter window-start set-window-start) +(gv-define-setter buffer-local-value (val var buf) + (macroexp-let2 nil v val + `(with-current-buffer ,buf (set (make-local-variable ,var) ,v)))) + ;;; Some occasionally handy extensions. ;; While several of the "places" below are not terribly useful for direct use, @@ -446,7 +456,10 @@ The return value is the last VAL in the list. ;;;###autoload (defmacro gv-ref (place) "Return a reference to PLACE. -This is like the `&' operator of the C language." +This is like the `&' operator of the C language. +Note: this only works reliably with lexical binding mode, except for very +simple PLACEs such as (function-symbol 'foo) which will also work in dynamic +binding mode." (gv-letplace (getter setter) place `(cons (lambda () ,getter) (lambda (gv--val) ,(funcall setter 'gv--val))))) |