Go to Emacs-Lisp Definition

Go to Emacs-Lisp Definition

[Nordlöw]

Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
symbol: function, variable, face, etc kind of like find-tag but using
Emacs own symbol database (hash-table)?

I know that I can achieve this in Vanilla Emacs with C-h f,v, but
direct jump (M-.) would be more user efficient!

Thanks,
Per Nordlöw

Re: Go to Emacs-Lisp Definition

[Helmut Eller]

* Nordlöw [2009-09-22 11:13+0200] writes:

> Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
> symbol: function, variable, face, etc kind of like find-tag but using
> Emacs own symbol database (hash-table)?
>
> I know that I can achieve this in Vanilla Emacs with C-h f,v, but
> direct jump (M-.) would be more user efficient!

I have this in my .emacs.  It's some random elisp hacking stuff.
Pick what you need.

Helmut

(defun elisp-disassemble (function)
  (interactive (list (function-called-at-point)))
  (disassemble function))

(defun elisp-pp (sexp)
  (with-output-to-temp-buffer "*Pp Eval Output*"
    (pp sexp)
    (with-current-buffer standard-output
      (emacs-lisp-mode))))

(defun elisp-macroexpand (form)
  (interactive (list (form-at-point 'sexp)))
  (elisp-pp (macroexpand form)))

(defun elisp-macroexpand-all (form)
  (interactive (list (form-at-point 'sexp)))
  (elisp-pp (cl-macroexpand-all form)))

(defun elisp-push-point-marker ()
  (require 'etags)
  (cond ((featurep 'xemacs)
         (push-tag-mark))
        (t (ring-insert find-tag-marker-ring (point-marker)))))

(defun elisp-pop-found-function ()
  (interactive)
  (cond ((featurep 'xemacs) (pop-tag-mark nil))
        (t (pop-tag-mark))))

(defun elisp-find-definition (name)
  "Jump to the definition of the function (or variable) at point."
  (interactive (list (thing-at-point 'symbol)))
  (cond (name
	 (let ((symbol (intern-soft name))
	       (search (lambda (fun sym)
			 (let* ((r (save-excursion (funcall fun sym)))
				(buffer (car r))
				(point (cdr r)))
			   (cond ((not point)
				  (error "Found no definition for %s in %s"
					 name buffer))
				 (t
				  (switch-to-buffer buffer)
				  (goto-char point)
				  (recenter 1)))))))
	   (cond ((fboundp symbol)
		  (elisp-push-point-marker)
		  (funcall search 'find-function-noselect symbol))
		 ((boundp symbol)
		  (elisp-push-point-marker)
		  (funcall search 'find-variable-noselect symbol))
		 (t
		  (message "Symbol not bound: %S" symbol)))))
  (t (message "No symbol at point"))))

(defun elisp-bytecompile-and-load ()
  (interactive)
  (or buffer-file-name
      (error "The buffer must be saved in a file first"))
  (require 'bytecomp)
  ;; Recompile if file or buffer has changed since last compilation.
  (when  (and (buffer-modified-p)
	      (y-or-n-p (format "save buffer %s first? " (buffer-name))))
      (save-buffer))
  (let ((filename (expand-file-name buffer-file-name)))
    (with-temp-buffer
      (byte-compile-file filename t))))

(defvar elisp-extra-keys 
  '(((kbd "C-c d")   'elisp-disassemble)
    ((kbd "C-c m")   'elisp-macroexpand)
    ((kbd "C-c M")   'elisp-macroexpand-all)
    ((kbd "C-c C-c") 'compile-defun)
    ((kbd "C-c C-k") 'elisp-bytecompile-and-load)
    ((kbd "C-c C-l") 'load-file)
    ((kbd "C-c p")   'pp-eval-last-sexp)
    ((kbd "M-.")     'elisp-find-definition)
    ((kbd "M-,")     'elisp-pop-found-function)
    ((kbd "C-c <")   'list-callers)))

(dolist (binding elisp-extra-keys)
  (let ((key (eval (car binding))) (val (eval (cadr binding))))
    (define-key emacs-lisp-mode-map key val)
    (define-key lisp-interaction-mode-map key val)))

Re: Go to Emacs-Lisp Definition

[Stefan Kamphausen]

Hi,

Nordlöw <per.nordlow@gmail.com> writes:

> Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
> symbol: function, variable, face, etc kind of like find-tag but using
> Emacs own symbol database (hash-table)?
>
> I know that I can achieve this in Vanilla Emacs with C-h f,v, but
> direct jump (M-.) would be more user efficient!

not sure, whether I understand your intentions but maybe find-function
and find-variable are your friends.  

Regards,
Stefan
-- 
Stefan Kamphausen --- http://www.skamphausen.de
a blessed +42 regexp of confusion (weapon in hand)
You hit. The format string crumbles and turns to dust.

Re: Go to Emacs-Lisp Definition

[Andreas Röhler]

Nordlöw wrote:
> Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
> symbol: function, variable, face, etc kind of like find-tag but using
> Emacs own symbol database (hash-table)?
>
> I know that I can achieve this in Vanilla Emacs with C-h f,v, but
> direct jump (M-.) would be more user efficient!
>
> Thanks,
> Per Nordlöw
>
>   


with output following C-h v or C-h f
I use `jump-to-form' - bound here to f12:

(defun jump-to-form ()
  (interactive)
  (if (featurep 'xemacs)
      (progn
    (forward-char 1)
    (let ((name (symbol-atpt))
          (file (progn (search-forward "\"" nil t 1)(thing-at-point
'filename))))
      (forward-char 1)
      (help-find-source-or-scroll-up (point))
      (switch-to-buffer (current-buffer))
      (kill-new name)
      (search-forward name)))
    (other-window 1)
    (forward-button 1)
    ;; (find-file (filename-atpt))
    (push-button)))

;;;;;;;;;

Re: Go to Emacs-Lisp Definition

[Andreas Politz]

Nordlöw <per.nordlow@gmail.com> writes:

> Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
> symbol: function, variable, face, etc kind of like find-tag but using
> Emacs own symbol database (hash-table)?
>
> I know that I can achieve this in Vanilla Emacs with C-h f,v, but
> direct jump (M-.) would be more user efficient!
>

Take a look at how `find-function' does it.  Here is the most
simple implementation I can think of.

(defun find-symbol (symbol)
  "Find the definition of SYMBOL, defaults to the symbol at point.
Prefer functions over variables over faces."
  (interactive
   (list (let ((symbol (thing-at-point 'symbol)))
           (intern (completing-read
                    (concat "Find symbol"
                            (and symbol
                                 (format " (default %s)" symbol))
                            ": ") obarray
                    #'(lambda (sym)
                        (or (fboundp sym)
                            (boundp sym)
                            (facep sym))) t)))))
  (find-function-do-it
   symbol
   (cond
    ((fboundp symbol) nil)
    ((boundp symbol) 'defvar)
    (t 'defface)) 'switch-to-buffer))
    
                       
-ap

Re: Go to Emacs-Lisp Definition

[Andreas Röhler]

Helmut Eller wrote:
> * Nordlöw [2009-09-22 11:13+0200] writes:
>
>   
>> Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
>> symbol: function, variable, face, etc kind of like find-tag but using
>> Emacs own symbol database (hash-table)?
>>
>> I know that I can achieve this in Vanilla Emacs with C-h f,v, but
>> direct jump (M-.) would be more user efficient!
>>     
>
> I have this in my .emacs.  It's some random elisp hacking stuff.
> Pick what you need.
>
> Helmut
>
> (defun elisp-disassemble (function)
>   
...

It's great, thanks a lot.  May you ask at emacs-devel to include it? -
my suggestion.

Took it into Emacs Lisp Bill Board

http://repo.or.cz/w/elbb.git
or better
http://repo.or.cz/w/elbb.git?a=tree;f=code;hb=HEAD

Andreas

Re: Go to Emacs-Lisp Definition

[Bernardo]

> Has anyone implemented a go to (lookup) definition of an Emacs-Lisp
> symbol: function, variable, face, etc kind of like find-tag but using
> Emacs own symbol database (hash-table)?
> 
> I know that I can achieve this in Vanilla Emacs with C-h f,v, but
> direct jump (M-.) would be more user efficient!

(possibly) outside Emacs:
   etags *.el

inside Emacs:
   M-x visit-tags-table RET /usr/share/emacs/23.1/lisp/TAGS RET

and M-. and friends should work