podar@sbcs.UUCP (Sunil Podar) (05/04/85)
I wanted to write a very simple mlisp function, but couldn't get it to do
what I wanted; This is for Gosling emacs on 4.2BSD.
Here is what I eventually settled with:
;-------------------------------------
(defun (forget-it buff-name
(setq buff-name (get-tty-string (concat ": delete-buffer ["
(current-buffer-name) "] ")))
(if (= buff-name "")
(delete-buffer (current-buffer-name))
(delete-buffer buff-name))))
;;;-------------------------------------
The problem is that I wanted to use "get-tty-buffer" in place of
"get-tty-string" so that name-completion would be provided, which is
a very useful (& sometimes essential) feature for many buffer names are
often very cryptic (e.g. **Scratch Stuff**) and "get-tty-string" needs
to have the entire name specified exactly. Moreover I wanted to provide
a default for which you merely had to press <return>, but get-tty-buffer
does not have provision for such, pressing return gives you a whole list
of buffers. One ugly way around is to have two separate functions(bound to
two keys <a no,no> , one for deleting current buffer & other for other
buffers. Another ugly way around is to first use a "get-tty-character" and
then if answer <> "" then ask-again, this time with no default &
get-tty-buffer.
In short, is there a way to give default to get-tty-buffer without having
to modify the c-code that handles buffers. I am sure the other similar
commands like "get-tty-file", etc. have the same problem, excepting of course
"get-tty-char.../string".
Any ideas? Thanks in advance. I think it is a fairly simple problem,
perhaps net.emacs should be spared the answers,if any,well I leave it
upto people.net.emacs.
--
Sunil Podar CSNET: podar@sbcs.csnet
SUNY at Stony Brook ARPA: podar%suny-sb.csnet@csnet-relay.arpa
UUCP: {allegra, hocsd, philabs, ogcvax} !sbcs!podarglenn@nsc.UUCP (Glenn Skinner) (05/09/85)
In article <271@sbcs.UUCP> podar@sbcs.UUCP (Sunil Podar) wanted to write
an MLisp function that used command completion to get a buffer name, but
that supplied a default buffer name if the user simply typed CR as a response.
The following function can be used to construct such a function. He suggested
that someone send him a solution by mail, but since the technique used is
nonobvious, I decided to post the solution. The basic idea is to use a local
keymap that binds everything to self-insert-and-exit to obtain a single
character. If this character is CR, we return the default buffer name.
Otherwise, we push back the character obtained, restore keymaps and use
get-tty-buffer to get the rest of the name. The function below assumes that
you have the UniPress V2.00 version of gosmacs -- it uses current-local-keymap.
If you have an older version, you'll have to kludge around it.
(defun
(get-defaulted-buffer-name default oldmap key buffer
(setq default (arg 1 ": get-defaulted-buffer-name "))
(setq oldmap (current-local-keymap)
(use-local-map "single-char-keymap")
(setq key "")
; It's important to use error-occurred here. Otherwise we could
; end up with a keymap that leaves us totally helpless!
(error-occurred
(setq key (get-tty-string ""))
)
(use-local-map oldmap)
(if (!= key "")
(progn
(push-back-string key)
(setq buffer (get-tty-buffer ""))
)
(setq buffer default)
)
buffer
)
)
(progn i oldmap
(define-keymap "single-char-keymap")
(setq oldmap (current-local-keymap))
(use-local-map "single-char-keymap")
(setq i 0)
(while (< i 0200)
(local-bind-to-key "self-insert-and-exit" i)
(setq i (+ i 1))
)
(use-local-map oldmap)
)
Caveat: I haven't actually tested this code. However, I've used code very
similar to it for other purposes.
-- Glenn Skinner
National Semiconductor, Microcomputer Systems Division
(408) 733-2600 x 335cdh@calmasd.UUCP (C. Douglas Hodges) (05/10/85)
> >From: podar@sbcs.UUCP (Sunil Podar) > Subject: a simple problem for 4.2 gosling-emacs > Date: 4 May 85 02:56:40 GMT > Organization: Computer Science Dept, SUNY@Stony Brook > > I wanted to write a very simple mlisp function, but couldn't get it to do > what I wanted; This is for Gosling emacs on 4.2BSD. > Here is what I eventually settled with: > ;------------------------------------- > (defun (forget-it buff-name > (setq buff-name (get-tty-string (concat ": delete-buffer [" > (current-buffer-name) "] "))) > (if (= buff-name "") > (delete-buffer (current-buffer-name)) > (delete-buffer buff-name)))) > ;;;------------------------------------- > > The problem is that I wanted to use "get-tty-buffer" in place of > "get-tty-string" so that name-completion would be provided, which is > a very useful (& sometimes essential) feature for many buffer names are > often very cryptic (e.g. **Scratch Stuff**) and "get-tty-string" needs > to have the entire name specified exactly. Moreover I wanted to provide > a default for which you merely had to press <return>, ....... I think the following does what you desire: (defun ; prompts the user for a buffer name (similar to "get-tty-buffer") ; except that it provides two ways to default to the current buffer: ; <CR> -- immediate default to current buffer name ; space, escape -- expand the current buffer name out for the user ; but do not return (give a chance to change it) (get-tty-buf-w/-default char buf-name prompt (if (error-occurred (setq prompt (arg 1))) (setq prompt ": buffer-name ") ) (message prompt) (setq char (get-tty-character)) (if (= char '\^M') (setq buf-name (current-buffer-name)) (progn (if (| (= char ' ') (= char '\e')) (push-back-string (current-buffer-name)) (push-back-character char) ) (setq buf-name (get-tty-buffer prompt)) ) ) buf-name ) ) (defun (forget-it (delete-buffer (get-tty-buf-w/-default ": delete-buffer ")) ) )