SGI Freeware 1999 August

home *** CD-ROM | disk | FTP | other *** search

/ SGI Freeware 1999 August / SGI Freeware 1999 August.iso / dist / fw_xemacs.idb / usr / freeware / lib / xemacs-20.4 / info / xemacs-faq.info-5.z / xemacs-faq.info-5

Wrap

GNU Info File | 1998-05-21 | 21.1 KB | 587 lines

This is Info file ../info/xemacs-faq.info, produced by Makeinfo version 1.68 from the input file xemacs-faq.texi. File: xemacs-faq.info, Node: Q5.1.7, Next: Q5.1.8, Prev: Q5.1.6, Up: Miscellaneous I like the the `do' form of cl, does it slow things down? ========================================================= It shouldn't. Here is what Dave Gillespie has to say about cl.el performance: Many of the advanced features of this package, such as `defun*', `loop', and `setf', are implemented as Lisp macros. In byte-compiled code, these complex notations will be expanded into equivalent Lisp code which is simple and efficient. For example, the forms (incf i n) (push x (car p)) are expanded at compile-time to the Lisp forms (setq i (+ i n)) (setcar p (cons x (car p))) which are the most efficient ways of doing these respective operations in Lisp. Thus, there is no performance penalty for using the more readable `incf' and `push' forms in your compiled code. *Interpreted* code, on the other hand, must expand these macros every time they are executed. For this reason it is strongly recommended that code making heavy use of macros be compiled. (The features labelled "Special Form" instead of "Function" in this manual are macros.) A loop using `incf' a hundred times will execute considerably faster if compiled, and will also garbage-collect less because the macro expansion will not have to be generated, used, and thrown away a hundred times. You can find out how a macro expands by using the `cl-prettyexpand' function. File: xemacs-faq.info, Node: Q5.1.8, Next: Q5.1.9, Prev: Q5.1.7, Up: Miscellaneous I like recursion, does it slow things down? =========================================== Yes. Emacs byte-compiler cannot do much to optimize recursion. But think well whether this is a real concern in Emacs. Much of the Emacs slowness comes from internal mechanisms such as redisplay, or from the fact that it is an interpreter. Please try not to make your code much uglier to gain a very small speed gain. It's not usually worth it. File: xemacs-faq.info, Node: Q5.1.9, Next: Q5.1.10, Prev: Q5.1.8, Up: Miscellaneous How do I put a glyph as annotation in a buffer? =============================================== Here is a solution that will insert the glyph annotation at the beginning of buffer: (make-annotation (make-glyph '([FORMAT :file FILE] [string :data "fallback-text"])) (point-min) 'text (current-buffer)) Replace `FORMAT' with an unquoted symbol representing the format of the image (e.g. `xpm', `xbm', `gif', `jpeg', etc.) Instead of `FILE', use the image file name (e.g. `/usr/local/lib/xemacs-20.2/etc/recycle.xpm'). You can turn this to a function (that optionally prompts you for a file name), and inserts the glyph at `(point)' instead of `(point-min)'. File: xemacs-faq.info, Node: Q5.1.10, Next: Q5.2.1, Prev: Q5.1.9, Up: Miscellaneous `map-extents' won't traverse all of my extents! =============================================== I tried to use `map-extents' to do an operation on all the extents in a region. However, it seems to quit after processing a random number of extents. Is it buggy? No. The documentation of `map-extents' states that it will iterate across the extents as long as FUNCTION returns `nil'. Unexperienced programmers often forget to return `nil' explicitly, which results in buggy code. For instance, the following code is supposed to delete all the extents in a buffer, and issue as many `fubar!' messages. (map-extents (lambda (ext ignore) (delete-extent ext) (message "fubar!"))) Instead, it will delete only the first extent, and stop right there - because `message' will return a non-nil value. The correct code is: (map-extents (lambda (ext ignore) (delete-extent ext) (message "fubar!") nil)) File: xemacs-faq.info, Node: Q5.2.1, Next: Q5.2.2, Prev: Q5.1.10, Up: Miscellaneous How do I turn off the sound? ============================ Add the following line to your `.emacs': (setq bell-volume 0) (setq sound-alist nil) That will make your XEmacs totally silent - even the default ding sound (TTY beep on TTY-s) will be gone. File: xemacs-faq.info, Node: Q5.2.2, Next: Q5.2.3, Prev: Q5.2.1, Up: Miscellaneous How do I get funky sounds instead of a boring beep? =================================================== Make sure your XEmacs was compiled with sound support, and then put this in your `.emacs': (load-default-sounds) The sound support in XEmacs 19.14 was greatly improved over previous versions. File: xemacs-faq.info, Node: Q5.2.3, Next: Q5.2.4, Prev: Q5.2.2, Up: Miscellaneous What's NAS, how do I get it? ============================ *Note Q2.0.3:: for an explanation of the "Network Audio System". File: xemacs-faq.info, Node: Q5.2.4, Next: Q5.3.1, Prev: Q5.2.3, Up: Miscellaneous Sunsite sounds don't play. ========================== I'm having some trouble with sounds I've downloaded from sunsite. They play when I run them through `showaudio' or cat them directly to `/dev/audio', but XEmacs refuses to play them. Markus Gutschke <gutschk@uni-muenster.de> writes: [Many of] These files have an (erroneous) 24byte header that tells about the format that they have been recorded in. If you cat them to `/dev/audio', the header will be ignored and the default behavior for /dev/audio will be used. This happens to be 8kHz uLaw. It is probably possible to fix the header by piping through `sox' and passing explicit parameters for specifying the sampling format; you then need to perform a 'null' conversion from SunAudio to SunAudio. File: xemacs-faq.info, Node: Q5.3.1, Next: Q5.3.2, Prev: Q5.2.4, Up: Miscellaneous How do you make XEmacs indent CL if-clauses correctly? ====================================================== I'd like XEmacs to indent all the clauses of a Common Lisp `if' the same amount instead of indenting the 3rd clause differently from the first two. One way is to add, to `.emacs': (put 'if 'lisp-indent-function nil) However, note that the package `cl-indent.el' that comes with XEmacs sets up this kind of indentation by default. `cl-indent' also knows about many other CL-specific forms. To use `cl-indent', one can do this: (load "cl-indent") (setq lisp-indent-function (function common-lisp-indent-function)) One can also customize `cl-indent.el' so it mimics the default `if' indentation `then' indented more than the `else'. Here's how: (put 'if 'common-lisp-indent-function '(nil nil &body)) Also, a new version (1.2) of `cl-indent.el' was posted to comp.emacs.xemacs on 12/9/94. This version includes more documentation than previous versions. This may prove useful if you need to customize any indent-functions. File: xemacs-faq.info, Node: Q5.3.2, Next: Q5.3.3, Prev: Q5.3.1, Up: Miscellaneous Fontifying hang when editing a postscript file. =============================================== When I try to edit a postscript file it gets stuck saying: `fontifying 'filename' (regexps....)' and it just sits there. If I press `C-c' in the window where XEmacs was started, it suddenly becomes alive again. This was caused by a bug in the Postscript font-lock regular expressions. It was fixed in 19.13. For earlier versions of XEmacs, have a look at your `.emacs' file. You will probably have a line like: (add-hook 'postscript-mode-hook 'turn-on-font-lock) Take it out, restart XEmacs, and it won't try to fontify your postscript files anymore. File: xemacs-faq.info, Node: Q5.3.3, Next: Q5.3.4, Prev: Q5.3.2, Up: Miscellaneous How can I print WYSIWYG a font-locked buffer? ============================================= Font-lock looks nice. How can I print (WYSIWYG) the highlighted document? The package `ps-print.el', which is now included with XEmacs, provides the ability to do this. The source code contains complete instructions on its use, in `<xemacs_src_root>/lisp/packages/ps-print.el'. File: xemacs-faq.info, Node: Q5.3.4, Next: Q5.3.5, Prev: Q5.3.3, Up: Miscellaneous Getting `M-x lpr' to work with postscript printer. ================================================== My printer is a Postscript printer and `lpr' only works for Postscript files, so how do I get `M-x lpr-region' and `M-x lpr-buffer' to work? Put something like this in your `.emacs': (setq lpr-command "a2ps") (setq lpr-switches '("-p" "-1")) If you don't use a2ps to convert ASCII to postscript (why not, it's free?), replace with the command you do use. Note also that some versions of a2ps require a `-Pprinter' to ensure spooling. File: xemacs-faq.info, Node: Q5.3.5, Next: Q5.3.6, Prev: Q5.3.4, Up: Miscellaneous How do I specify the paths that XEmacs uses for finding files? ============================================================== You can specify what paths to use by using a number of different flags when running configure. See the section MAKE VARIABLES in the top-level file INSTALL in the XEmacs distribution for a listing of those flags. Most of the time, however, the simplest fix is: *do not* specify paths as you might for GNU Emacs. XEmacs can generally determine the necessary paths dynamically at run time. The only path that generally needs to be specified is the root directory to install into. That can be specified by passing the `--prefix' flag to configure. For a description of the XEmacs install tree, please consult the `NEWS' file. File: xemacs-faq.info, Node: Q5.3.6, Next: Q5.3.7, Prev: Q5.3.5, Up: Miscellaneous [This question intentionally left blank] ======================================== Obsolete question, left blank to avoid renumbering. File: xemacs-faq.info, Node: Q5.3.7, Next: Q5.3.8, Prev: Q5.3.6, Up: Miscellaneous Can I have the end of the buffer delimited in some way? ======================================================= Say, with: `[END]'? Try this: (let ((ext (make-extent (point-min) (point-max)))) (set-extent-property ext 'start-closed t) (set-extent-property ext 'end-closed t) (set-extent-property ext 'detachable nil) (set-extent-end-glyph ext (make-glyph [string :data "[END]"]))) Since this is XEmacs, you can specify an icon to be shown on window-system devices. To do so, change the `make-glyph' call to something like this: (make-glyph '([xpm :file "~/something.xpm"] [string :data "[END]"])) You can inline the XPM definition yourself by specifying `:data' instead of `:file'. Here is such a full-featured version that works on both X and TTY devices: (let ((ext (make-extent (point-min) (point-max)))) (set-extent-property ext 'start-closed t) (set-extent-property ext 'end-closed t) (set-extent-property ext 'detachable nil) (set-extent-end-glyph ext (make-glyph '([xpm :data "\ /* XPM */ static char* eye = { \"20 11 7 2\", \"__ c None\" \"_` c #7f7f7f\", \"_a c #fefefe\", \"_b c #7f0000\", \"_c c #fefe00\", \"_d c #fe0000\", \"_e c #bfbfbf\", \"___________`_`_`___b_b_b_b_________`____\", \"_________`_`_`___b_c_c_c_b_b____________\", \"_____`_`_`_e___b_b_c_c_c___b___b_______`\", \"___`_`_e_a___b_b_d___b___b___b___b______\", \"_`_`_e_a_e___b_b_d_b___b___b___b___b____\", \"_`_`_a_e_a___b_b_d___b___b___b___b___b__\", \"_`_`_e_a_e___b_b_d_b___b___b___b___b_b__\", \"___`_`_e_a___b_b_b_d_c___b___b___d_b____\", \"_____`_`_e_e___b_b_b_d_c___b_b_d_b______\", \"_`_____`_`_`_`___b_b_b_d_d_d_d_b________\", \"___`_____`_`_`_`___b_b_b_b_b_b__________\", } ;"] [string :data "[END]"])))) Note that you might want to make this a function, and put it to a hook. We leave that as an excercise for the reader. File: xemacs-faq.info, Node: Q5.3.8, Next: Q5.3.9, Prev: Q5.3.7, Up: Miscellaneous How do I insert today's date into a buffer? =========================================== Like this: (insert (current-time-string)) File: xemacs-faq.info, Node: Q5.3.9, Next: Q5.3.10, Prev: Q5.3.8, Up: Miscellaneous Are only certain syntactic character classes available for abbrevs? =================================================================== Markus Gutschke <gutschk@uni-muenster.de> writes: Yes, abbrevs only expands word-syntax strings. While XEmacs does not prevent you from defining (e.g. with `C-x a g' or `C-x a l') abbrevs that contain special characters, it will refuse to expand them. So you need to ensure, that the abbreviation contains letters and digits only. This means that `xd', `d5', and `5d' are valid abbrevs, but `&d', and `x d' are not. If this sounds confusing to you, (re-)read the online documentation for abbrevs (`C-h i m XEmacs RET m Abbrevs RET'), and then come back and read this question/answer again. Newsflash: this restriction has been lifted, starting with XEmacs 20.3, which is currently in beta. Hrvoje Niksic <hniksic@srce.hr> will appreciate it if you download a beta, try out whether abbreviations work like you expect them to, and let him know. File: xemacs-faq.info, Node: Q5.3.10, Next: Q5.3.11, Prev: Q5.3.9, Up: Miscellaneous How can I get those oh-so-neat X-Face lines? ============================================ Firstly there is an ftp site which describes X-faces and has the associated tools mentioned below, at <URL:ftp://ftp.cs.indiana.edu:/pub/faces/>. Then the steps are 1. Create 48x48x1 bitmap with your favorite tool 2. Convert to "icon" format using one of xbm2ikon, pbmtoicon, etc., and then compile the face. 3. cat file.xbm | xbm2ikon |compface > file.face 4. Then be sure to quote things that are necessary for emacs strings: cat ./file.face | sed 's/\\/\\\\/g' | sed 's/\"/\\\"/g' > ./file.face.quoted 5. Then set up emacs to include the file as a mail header - there were a couple of suggestions here--either something like: (setq mail-default-headers "X-Face: <Ugly looking text string here>") Or, alternatively, as: (defun mail-insert-x-face () (save-excursion (goto-char (point-min)) (search-forward mail-header-separator) (beginning-of-line) (insert "X-Face:") (insert-file-contents "~/.face"))) (add-hook 'mail-setup-hook 'mail-insert-x-face) However, 2 things might be wrong: Some versions of pbmtoicon produces some header lines that is not expected by the version of compface that I grabbed. So I found I had to include a `tail +3' in the pipeline like this: cat file.xbm | xbm2ikon | tail +3 |compface > file.face Some people have also found that if one uses the `(insert-file)' method, one should NOT quote the face string using the sed script . It might also be helpful to use Stig's <stig@hackvan.com> script (included in the compface distribution at XEmacs.org) to do the conversion. For convenience xbm2xface is available for anonymous FTP at <URL:ftp://ftp.miranova.com/pub/xemacs/xbm2xface.pl>. Contributors for this item: Paul Emsley, Ricardo Marek, Amir J. Katz, Glen McCort, Heinz Uphoff, Peter Arius, Paul Harrison, and Vegard Vesterheim File: xemacs-faq.info, Node: Q5.3.11, Next: Q5.3.12, Prev: Q5.3.10, Up: Miscellaneous How do I add new Info directories? ================================== You use something like: (setq Info-directory-list (cons (expand-file-name "~/info") Info-default-directory-list)) David Masterson <davidm@prism.kla.com> writes: Emacs Info and XEmacs Info do many things differently. If you're trying to support a number of versions of Emacs, here are some notes to remember: 1. Emacs Info scans `Info-directory-list' from right-to-left while XEmacs Info reads it from left-to-right, so append to the *correct* end of the list. 2. Use `Info-default-directory-list' to initialize `Info-directory-list' *if* it is available at startup, but not all Emacsen define it. 3. Emacs Info looks for a standard `dir' file in each of the directories scanned from #1 and magically concatenates them together. 4. XEmacs Info looks for a `localdir' file (which consists of just the menu entries from a `dir' file) in each of the directories scanned from #1 (except the first), does a simple concatentation of them, and magically attaches the resulting list to the end of the menu in the `dir' file in the first directory. Another alternative is to convert the documentation to HTML with texi2html and read it from a web browser like Lynx or W3. File: xemacs-faq.info, Node: Q5.3.12, Prev: Q5.3.11, Up: Miscellaneous What do I need to change to make printing work? =============================================== For regular printing there are two variables that can be customized. `lpr-command' This should be set to a command that takes standard input and sends it to a printer. Something like: (setq lpr-command "lp") `lpr-switches' This should be set to a list that contains whatever the print command requires to do its job. Something like: (setq lpr-switches '("-depson")) For postscript printing there are three analogous variables to customize. `ps-lpr-command' This should be set to a command that takes postscript on standard input and directs it to a postscript printer. `ps-lpr-switches' This should be set to a list of switches required for `ps-lpr-command' to do its job. `ps-print-color-p' This boolean variable should be set `t' if printing will be done in color, otherwise it should be set to `nil'. NOTE: It is an undocumented limitation in XEmacs that postscript printing (the `Pretty Print Buffer' menu item) *requires* a window system environment. It cannot be used outside of X11. File: xemacs-faq.info, Node: Current Events, Prev: Miscellaneous, Up: Top What the Future Holds ********************* This is part 6 of the XEmacs Frequently Asked Questions list. This section will change monthly, and contains any interesting items that have transpired over the previous month. If you are reading this from the XEmacs distribution, please see the version on the Web or archived at the various FAQ FTP sites, as this file is surely out of date. * Menu: * Q6.0.1:: What is new in 20.2? * Q6.0.2:: What is new in 20.3? * Q6.0.3:: Procedural changes in XEmacs development. File: xemacs-faq.info, Node: Q6.0.1, Next: Q6.0.2, Prev: Current Events, Up: Current Events What is new in 20.2? ==================== The biggest changes in 20.2 include intergration of EFS (the next generation of ange-ftp) and AUC Tex (the Emacs subsystem that includes a major mode for editing Tex and LaTeX, and a lot of other stuff). Many bugs from 20.0 have been fixed for this release. 20.2 also contains a new system for customizing XEmacs options, invoked via `M-x customize'. XEmacs 20.2 is the development release (20.0 was beta), and is no longer considered unstable. File: xemacs-faq.info, Node: Q6.0.2, Next: Q6.0.3, Prev: Q6.0.1, Up: Current Events What is new in 20.3? ==================== XEmacs 20.3 will be released in November 1997. It will contain many bugfixes, and a number of new features, including Autoconf 2 based configuration, multiple TTY frames, further customizations, synches with GNU Emacs 20, advanced Perl-like regexp features, and more. XEmacs 20.3 will be the first non-beta v20 release, and will be the basis for all further development. File: xemacs-faq.info, Node: Q6.0.3, Prev: Q6.0.2, Up: Current Events Procedural changes in XEmacs development. ========================================= 1. Discussion about the development of XEmacs occurs on the xemacs-beta mailing list. Subscriptions to this list will now be fully automated instead of being handled by hand. Send a mail message to <xemacs-beta-request@xemacs.org> with a subject of subscribe to join the list. Please note this is a developers mailing list for people who have an active interest in the development process. The discussion of NT XEmacs development is taking place on a separate mailing list. Send mail to <xemacs-nt-request@xemacs.org> to subscribe. 2. Due to the long development cycle in between releases, it has been decided that intermediate versions will be made available in source only form for the truly interested. XEmacs 19.16 was the last 19 release, basically consisting of 19.15 plus the collected bugfixes. 3. As of December 1996, Steve Baur <steve@altair.xemacs.org> has become the lead maintainer of XEmacs.