# C. How to...

This is a collection of "How to" topics, each with short discussion. The following categories of topics are available:

- Initialization - Change the default behavior of Elvis
- Word Completion - Alter word completion via the `Tab` key
- Whitespace - The relationship between tabs and spaces
- Buffers - Cut buffers and edit buffers
- X-Windows - The "x11" user interface
- Windows95/98/NT - The "windows" user interface
- Miscellany - Things that didn't fit anywhere else
- Contacts - How to contact the authors

If you're using Elvis to view this file, you can search for a topic simply by using the / command. To limit the search to topic lines only, begin the regular expression with "^<dt>.*". For example you could search for "spaces" in a topic line via the following:

    	/^<dt>.*spaces

Sometimes there are multiple topics that use the same word or phrase. If the first one that it finds isn't the one you want, then you can use the n command to find the next one.

In addition, the lib/elvis.ali script distributed with Elvis contains a :howto alias which loads this file and searches for a given topic. The aliases from lib/elvis.ali are loaded automatically, so you should be able to display any topic in a a separate window via a command such as this:

    	:howto spaces

## C.1 Initialization

Initialization for each file
  The lib/elvis.arf file is executed after a file has been read; you can put file initialization commands there.

  Alternatively, you could use the :au command, with an event such as BufRead.

Store an explicit display mode inside a file
  The simplest way is to enable modelines by setting the modeline option, and then add a modeline to the file which sets the bufdisplay option to the desired display mode. For example, if you have a lex(1) source file with the extension ".l", and you want it to be highlighted as C code, then you could add the following line to the end of the file:

      	/* ex:set bufdisplay="syntax c": */

  Alternatively, you could modify the elvis.arf script to detect your type of file, and set the `bufdisplay` option appropriately. For example, adding the following line into `elvis.arf` would cause any file that looks like a patch to be displayed using "syntax cdiff"

      	1s/---\|\*\*\*/set bufdisplay="syntax cdiff"/x

  If you don't want to modify `elvis.arf`, you could achieve a similar effect via the BufReadPost autocmd event.

Make file initialization be language-sensitive
  If the filename extension indicates the file's language, and the language is described in the lib/elvis.syn file, then you can use the `knownsyntax()` function to check the language, like this:

      	:if knownsyntax(filename) == "perl"
      	:then set ccprg="perl -c ($1?$1:$2) 2>&1 | perlerr"

  (The `perlerr` Perl script converts perl's error messages into a form that Elvis can parse. It is given in the Tips chapter.)

  You could also use the `dirext()` function to check the filename extension directly, instead of `knownsyntax()`; it doesn't depend on the lib/elvis.syn file. As a last resort, you might consider using the `x` flag of the :s command.

Change the default settings
  Before the first buffer is loaded or the first window is created, any buffer/window options you set will be used as the defaults for the buffers/windows that are created later. In other words, although setting a buffer-specific option like equalprg or a window-specific option like ruler interactively will only affect that buffer or window, setting the same option in the lib/elvis.ini or `~/.exrc` file changes the default for all buffers/windows.

  However, the lib/elvis.brf and lib/elvis.arf files typically change some of those options, so the defaults might not be used very long before they're changed.

Have a separate ~/.exrc and ~/.elvisrc file under Unix
  This is easy. The lib/elvis.ini file controls this, and the default version does it in a very convenient way: It looks first for `.elvisrc` and runs it if it exists; else it looks for `.exrc` and runs that.

  If you want Elvis to run both of them, then add the following line to your `.elvisrc` file:

      	:source ~/.exrc

Display HTML files in "syntax" mode by default
  In previous versions of Elvis, this was tricky because Elvis' online manual is written in HTML and you certainly want it to be formatted normally. Also, if you download an HTML file from the web (using Elvis as a browser) then you probably want it to be formatted via the "html" display mode. So you only want to change the behavior of local, non-Elvis HTML files.

  Now Elvis has a prefersyntax option, which makes this pretty easy. Just run "`:set prefersyntax=writable`".

Save the current settings as the defaults
  Run :mkexrc.
Mix hand-coded settings with the :mkexrc-generated commands
  You can use :mkexrc to save settings and also have a separate file containing hand-coded commands. Hand-coded settings could be useful, for example, if you want to use :if to define aliases or options differently, depending on which user interface you're using.

  The :mkexrc command always completely overwrites whatever file it writes to. Because of this, you must save your hand-coded initialization commands in a separate file. In the following example, we'll store the hand-coded commands in ~/.elvisrc and allow :mkexrc to store the automatically generated commands in ~/.elvismkexrc.

  1. Run "`elvis ~/.elvisrc`". This starts Elvis, loads your settings, and then starts editing the ~/.elvisrc file.
  2. Give Elvis the command "`:mkexrc ~/.elvismkexrc`". This will change the mkexrcfile option to ~/.elvismkexrc, and then write your current settings out to that file. The settings will include "`set mkexrcfile=~/.elvismkexrc`", so when you load those settings again later, ~/.elvismkexrc will become the default file used by the :mkexrc command.
  3. Delete all of the settings from ~/.elvisrc, and replace them with a single "`source ~/.elvismkexrc`" command line. This way, when Elvis runs the ~/.elvisrc script during startup, it'll automatically run the commands in ~/.elvismkexrc too.
  4. Append any other hand-coded initialization steps after the above :source command.

## C.2 Word Completion

Disable word completion on the ex command line
  You need to set the inputtab option for the `(Elvis ex history)` buffer to "tab". You can do that via the following command:

      	:(Elvis ex history)set inputtab=tab

Disable identifier completion on the regular expression prompt line
  This is similar to word completion on the ex command line. To disable it, you need to set the inputtab option for the `(Elvis regexp history)` buffer, like this:

      	:(Elvis regexp history)set inputtab=tab

Enable identifier completion in normal edit buffers
  Set the buffer's inputtab option to "identifier". To make this the default, set it in the `.exrc` file (or `elvis.rc` for non-Unix systems). The command is:

      	:set inputtab=identifier

  After that, each time you hit the <`Tab`> key Elvis will search through the tags file for any matching tags, and add as many characters as possible. If it completes the entire tag name, it does not append a space or other character, which is a little different from other types of name completion. Also, in the syntax display mode it will not attempt completion if the partial word happens to be a complete keyword or "other" word.

## C.3 Whitespace

Use spaces instead of tabs
  In the traditional vi, the only way to use spaces instead of tabs was to set the tabstop option to the largest possible value, and then :map ^I to ^T. This made existing tabbed files look bad, and it didn't work well for tabs embedded in a line (instead of just in the line's indentation whitespace). Elvis has a better way.

  In Elvis, you can set the inputtab option to "spaces" to make the `<Tab>` key insert the appropriate number of spaces into a line. This works even if the cursor isn't in the line's indentation whitespace.

  In addition, the autotab option controls the shifting commands (the :< and :> commands in ex, and the < and > operators in visual mode). To make those commands use only spaces, autotab should be off.

      	:set inputtab=spaces noautotab

  To convert existing files to use only spaces, you should use an external program such as "`col -bx`" under Unix. Alternatively, you can use Elvis to change the indentation (but not tabs elsewhere in a line) to use only spaces by shifting the entire file right, and then left again while the noautotab setting is in effect.

Change the tabstops
  Many people don't like the fact that the `<Tab>` key indents text by 8 columns. That's so wide that it quickly pushes the writer's source code off the right edge of the screen.

  However, you almost certainly do not want to change the tabstop option because most other software, and most printers and terminals, also assume that tabs are 8 characters wide. If you edit files with `tabstop` set to 4 or 5, then your files will look very strange when viewed with anything other than Elvis, or by anyone other than you. So leave `tabstop=8`.

  Instead, set the shiftwidth option to the desired indentation amount, and either get in the habit of typing ^T to increase indentation, or :map! the `<Tab>` key to ^T in input mode.

      	:set shiftwidth=5
      	:map! ^V^I ^V^T

  Note that when you're typing in the above `:map` command, you'll need to type an extra `^V` before each `^V` or `^T`.

  Also, this map has the unfortunate side-effect of making the `<Tab>` increase indentation even if the cursor is somewhere later in the line (unless you type ^V before it). This is one good reason to skip the map, and get in the habit of using `^T` to increase indentation. The autotab option helps here, too.

Erase text immediately when backspacing
  The cleantext option tells Elvis when to delete text that you've backspaced over. Try "`:set cleantext=long,bs,ex`".

## C.4 Buffers

Switch to a different buffer in the same window
  This is easier than you might think. On an ex command line, if you give an address but no command then Elvis will move the cursor to there. So to switch buffers all you need to do is give an address that's in a different buffer. In Elvis, you do this by giving the buffer's name (or number) in parentheses (and the closing parenthesis is optional). For example, to switch to buffer #1 all you need to do is...

      	:(#1

  Or you can switch to "main.c" like this:

      	:(main.c

  Of course, the buffer must exist before you can switch to it. Another thing to keep in mind is, switching buffers doesn't necessarily force you to save the old buffer first. Any changes you made to the old buffer are not lost -- you can switch back to the original buffer again if you wish.

Display an edit buffer (or cut buffer) in a separate window
  This is similar to switching edit buffers (the previous topic). The main difference is that instead of giving no command, you should give the :split command. In this context, the closing parenthesis is required.

      	:(#1)split

  Or, create a window showing the "main.c" buffer:

      	:(main.c)split

Edit a cut buffer
  Editing a cut buffer can be handy when you're trying to fix a defective macro. This is possible in Elvis, because Elvis uses an ordinary edit buffer to store the contents of a cut buffer. The names of the cut buffers are of the form `(Elvis cut buffer X)`, where X is the name of the cut buffer (a single letter or digit). Consequently, you could create a window showing cut buffer `"a` like this:

      	:(Elvis cut buffer a)split

  Of course, the `"a` cut buffer must exist for this to work.

  Since the name is so long, Elvis supports a special short-hand notation for cut buffer names. In parentheses, if the first character is " and the remainder of the buffer name is a single letter, then Elvis uses the buffer which contains that cut buffer's contents. The following command also creates a window showing the `"a` cut buffer:

      	:("a)sp

  Elvis doesn't store "undo" versions for cut buffers, and you can't yank a buffer into itself. Other than that, editing should be pretty normal. The type of data in the buffer (characters, lines, or rectangle) is stored in an option named putstyle.

Free an edit buffer
  Elvis has no command for discarding old edit buffers. Under some circumstances it will free them automatically, if they aren't being used. It rarely matters, though.

## C.5 X-Windows

Run Elvis in an xterm instead of creating a new window
  You can force Elvis to use the termcap interface by adding a `-Gtermcap` flag. If you do this often, you may wish to create a shell script, alias, or shell function which runs Elvis with `-Gtermcap`. Here's an example of shell script:

      	#!/bin/sh
      	exec elvis -Gtermcap "$@"

  A more elegant solution uses the $ELVISGUI environment variable:

      	#!/bin/sh
      	ELVISGUI=termcap exec elvis "$@"

  If you never want to use the "x11" user interface, then you should probably reconfigure Elvis to leave it out. This will make Elvis considerably smaller. To do this, go into the directory where Elvis' source code resides and execute the following shell commands:

      	make clean
      	./configure --with-x=no
      	make

Run Elvis from a [Start] menu
  The only tricky thing about this is, Elvis implements both the text & graphic interfaces in the same executable. When Elvis is invoked from something other than an xterm (or equivalent) it runs in text mode be default. (This was done because most Linux distributions set the DISPLAY environment variable even if you're logged in on a text console. Elvis used to start in graphic mode on some other virtual console, which was very confusing. By checking whether it was started from an xterm, Elvis can avoid that problem.)

  The solution is to add an explicit `-Gx11` command line flag when it is invoked from a window manager's menu.

Make the text cursor more visible under X11
  For a notebook computer, the normal blinking cursor may be hard to see. You can make it stop blinking by adding the following command to your `.exrc` file:

      	:set blinktime=0

Indicate when Elvis owns the current X11 selection
  The cursor can be configured to have a special color whenever Elvis owns the current selection. To do this, use the :color command to set both the foreground and background color of the cursor. The "background" color will be used when Elvis owns the selection, and the "foreground" color will be used otherwise. Here's an example which turns the cursor green when Elvis owns the selection:

      	:color cursor red on green

Change the default font size
  In your `.exrc` file, you can set the font, boldfont, and italicfont options to anything you want. (Fixed-pitch only!) These settings will override the defaults. If you set only the `font` and leave the others unset, then Elvis will derive the others from the normal font.

      	:set font=7x14

  If you just want to use a smaller size of the Courier font, you can use the :courier alias. It takes a single parameter: the point size of the font to use. The default font is 18-point Courier, and most systems also have 12-, 14-, and 24-point Courier fonts which work well.

      	:courier 14

Set a font for the toolbar buttons.
  By default, the X11 toolbar uses a font named "variable" which is usually an alias to a small, readable, variable-pitch font. If your X server has no font named "variable" then you must configure Elvis to use a different font. You may also simply prefer a different font.

  The simplest way to change the font is to pass Elvis a `-fc` fontname parameter. I suggest you use that to experiment with the available fonts, to find one you like. (You can use the standard `xlsfonts` program to list the available fonts.)

  To make the change permanent, you can either set the controlfont option in your ~/.exrc file, or you can set the elvis.control.font resource in your ~/.Xdefaults file.

Run a program from within Elvis, in parallel, under X11
  The tricky part here is that Elvis tries to read the program's stdout and stderr, so the output can be displayed in Elvis' window. To do that, Elvis would have to wait until after all text has been read from stdout/stderr... but you don't want Elvis to wait! So to run in parallel, you must redirect the program's stdout/stderr to /dev/null, like this:

      	:!xeyes >/dev/null 2>&1 &

  If you want to write data out to the program (`:w !program`) then it becomes even more complex. This is because pipes can only contain a finite amount of data, so when Elvis is redirecting stdin as well as stdout/stderr, it uses a temporary file for stdin. Elvis deletes that file as soon as the program returns -- which, for a program run in parallel, happens immediately even though the program hasn't had a chance to read the data from that file yet. The solution is to write the data into a temporary file sequentially, and then start a parallel command line which runs the program and then deletes the temporary file, like this:

      	:w !cat >$$; (xv $$; rm $$) >/dev/null 2>&1 &

  Yes, that's nasty. I plan to clean that up some day, by making Elvis smart enough to avoid reading stdout/stderr when the command line ends with a '&' character.

Run an interactive program in an Elvis window under X11
  Sadly, this can't be done with Elvis' "x11" user interface because Elvis' windows don't have a built-in terminal emulator. This is expected to be added for Elvis 2.3, but that doesn't help you now.

  However, by using the "termcap" interface inside an xterm, you should be able to run interactive programs such as "crypt" or "pgp" exactly as you can under vi. In an xterm (or any other terminal emulator), just run "`elvis -Gtermcap`" instead of plain "`elvis`".

Configure XFree86 to use a mouse's scroll wheel
  Elvis expects the scroll wheel to act like mouse buttons 4 and 5. To make XFree86 present scroll wheel events this way, your XF86Config file's "Pointer" section should contain ``Buttons 5`' and ``ZAxisMapping 4 5`'. Also, for serial mice you may need to specify ``Protocol "Intellimouse"`'; for PS/2 mice, try
  ``Protocol "IMPS/2"`'.

  The Rxvt terminal emulator and most Gtk/Gnome programs will also support the scroll wheel when it is configured this way. In addition, many other programs can be configured to support it by specifying the appropriate translations in their app-defaults. For example, Netscape can be configured to respond to the scroll wheel by inserting the following lines into the `Netscape*drawingArea.translations` resource string:

          <Btn4Down>:    LineUp()            \
                         LineUp()            \
                         LineUp()            \
                         LineUp()            \
                         LineUp()            \n\
          <Btn5Down>:    LineDown()          \
                         LineDown()          \
                         LineDown()          \
                         LineDown()          \
                         LineDown()          \n\

  There is also a program named "imwheel" which can be configured to translate wheel motions into `<PgUP>` and `<PgDn>` keystrokes (or other keys) for specific applications.

## C.6 Windows95/98/NT

Set the initial working directory
  Create a shortcut to WinElvis, and then edit the shortcut's properties. The "Start in" property gives the program's initial working directory.
Change the working directory each time a file is loaded
  First, let me say that I don't recommend this because the real vi doesn't behave like this, so it is likely to confuse some people.

  But it you really want to do this, then you should add the following line to the end of your lib/elvis.arf file:

      	try cd (dirdir(filename))

Select whole lines in WinElvis
  To select whole lines in WinElvis, move the mouse pointer to the window's left margin. The mouse pointer should change shape when you're in the margin. Click the left mouse button there to begin marking lines; hold the button as you move the mouse to the other end of the range of lines and then release it.
Select a rectangular area in WinElvis
  There are two ways to do this. The first is by using the `right` mouse button; the other is by holding down the `<Alt>` key as you use the `left` mouse button.
Assign a printer port to a Windows print queue
  Windows98 has no PRN: device for sending raw printer data to a printer; all printing must go through the normal Windows print queue. That's fine if you're using the "windows" lptype, but if you want to use one of the other printer types such as "ps", "ps2", or "hp", then you need to jump through a few hoops.

  Although there is no PRN: device, Windows98 does allow you to associate an LPTn: device with a print queue, via mechanism called "capturing a printer port". I suggest you configure your computer's default print queue to capture LPT9:, and the set Elvis' lpout option to "LPT9". The steps for capturing the printer port are:

  1. From Windows' "Start" button, select "Settings"->"Printers".
  2. Right-click on your default printer, and select "Properties".
  3. In the properties dialog, go to the "Details" tab.
  4. Click "Capture Printer Port...".
  5. In the capture dialog, set the "Device" to "LPT9". Leave the "Path" field empty. The "Reconnect at logon" checkbox should have a checkmark so you don't need to repeat this every time you start Windows.
  6. Click "OK" to exit the capture dialog.
  7. Click "OK" to exit the properties dialog.

  After that, you just need to set up Elvis. Give Elvis the command "`:set lpout=lpt9`", and then "`:mkexrc`". You're done!

Associate file types with WinElvis
  To make Windows use WinElvis as the default editor of a given type file, you must associate the Elvis action with the file type. (The file type is determined by the filename's extension.) To create this association, perform the following steps:
  1. Open a directory window. Any directory will work; it doesn't necessarily have to be the one containing the new type of file.
  2. Select the "View->Folder Options..." menu item. This should bring up a dialog window.
  3. In the dialog window, select the "File types" tab.
  4. Hopefully the file type already exists in the "Registered file types" list. The list is sorted by extension, which is a little unfortunate since the extensions are normally hidden. If you can't find the file type in the list, then use the "New Type..." button to add it; but if you can find it, then highlight it and click the "Edit..." button. Either way, this should bring up a dialog which contains a (possibly empty) list if "Actions" for that file type.
  5. Click the "New..." button, below the "Actions" list. This will bring up yet another dialog.
  6. In the "New Action" dialog's "Action" field, put the text "Open with Elvis".
  7. In the "Application used to perform action" field, you need to put the full pathname of WinElvis in double-quotes (use the "Browse..." button for this), with a space and a double-quoted "%1" appended to indicate how the filename is passed into Elvis. For example, if WinElvis is located in C:\usr\bin, then this field should look like this:

         	"C:\usr\bin\WinElvis.exe" "%1"

  8. The "Use DDE" box should be unchecked.
  9. Press the "New Action" dialog's "OK" button. This should return you to the "New File Type" or "Edit File Type" dialog.
  10. The "Open with Elvis" action should now appear in the "Actions" list. Highlight it, and then click "Set Default" to make it be the default action. The default action is displayed in boldface in that list.
  11. Click the "OK" button to close the "New File Type" or "Edit File Type" dialog.
  12. If you want to add any more file types, then go back to step 4. Otherwise, click the "OK" button to close the "Folder Options" dialog.

  That should be all that is required. Double-clicking on files of that type will now cause WinElvis to open that file, and if you right-click on the file you'll see "Open with Elvis" as one of the options.

## C.7 Miscellany

Test for certain text within a file
  This is sometimes handy in scripts and aliases. For example, the elvis.arf script uses this to detect mode lines and the "hash pling" header on other types of scripts, such as shell scripts which start with "`#!/bin/sh`".

  One nice trick is to use the `x` flag of Elvis' :s command. It not only detects text, but can incorporate that text into the commands. For example, to compute the total of all numbers in all lines, you could...

      	:set t=0
      	:%s/\<[[:digit:]]\+\>/let t = t + &/gx
      	:set t?

  Note that this series of commands does not affect the edit buffer. The `x` flag prevents the substitution from taking place; the replacement text is executed instead.

  You can also use the :try command to run a search command, and then use :then and :else to act differently depending on whether the search succeeded or not.

      	:try /Yow!
      	:then echo Zippy was here
      	:else echo Where in the world is Zippy the Pinhead?

  You can also use the `current("word")` and `line()` functions to fetch the word at the cursor location, or a whole line, respectively.

      	:let w=current("word")
      	:let l=line(1)

Find the short name (or group name) of an option
  Finding the long name of an option is easy, thanks to name completion. To find the short name of an option, or the name of its group, run the :set! command (with a `!`) and the long option name, followed by a `?` character. (For non-Boolean options, the `?` is optional.)

      	:set! wrapmargin?

  This will produce output like "win.wm=0", indicating that the short name is "wm", the group name is "win" (so each window has its own margin), and the value is 0.

Recover files after a crash
  This is described in the Sessions chapter of the manual. Briefly, run "`elvis -r`" to start a new Elvis process on the old session file, and then use the :buffer command to list the buffers. You can then use other commands to save those buffers; for example, to save a buffer named "main.c" into a file named "main.c.recovered", you would give this command:

      	:(main.c)w main.c.recovered

Recognize error messages with an unusual format
  Elvis' :make and :cc commands assume that all error messages have a format that resembles that of gcc: A file name and line number appear at the beginning of the line (possibly with some punctuation or the word "line" mixed in), an optional "error" or "warning" code, and then the description of the error to finish the line. Elvis is very good at parsing messages that use formats which resemble this, but there is no explicit way to make Elvis parse any other format.

  However, it is usually possible to construct a little "filter" program to convert other error message formats into one that Elvis can recognize. The Tips chapter has an example of how to make Elvis handle PERL's error messages.

Input non-ASCII characters
  Elvis supports several ways to enter non-ASCII characters:
  - If your keyboard driver supports entry of non-ASCII characters, then that method should work in Elvis. However, "dead keys" have been reported to cause trouble.
  - Digraphs combine two ASCII characters to form a single non-ASCII character. See the :digraph command, digraph option, and the discussion in the Input Mode chapter. Briefly, the secret is to type `<Ctrl-K>` and then the two ASCII characters that you want to combine, such as `<Ctrl-K><n><~>` for "ñ".
  - You can type `<Ctrl-X>` followed by two hex characters to enter any byte into the edit buffer... provided you know the hex code for the character you want, of course.

  If you're having trouble displaying non-ASCII characters, then you may want to look into the nonascii option. Also, on Unix systems you should verify that your terminal is configured correctly (8 bits, not 7 -- and the Latin-1 character set is installed).

Change the default address range for a command
  This is sometimes desirable in an alias. For example the :w command writes all lines by default, but :s alters only one line by default. You may want to write a macro that uses both of them with the same default, or just one of them with a different default.

  The most straightforward way to do this is to use the !(default)% notation. Specifically, !(.)% will make any command in an alias default to using just the current line, and !(%)% will make any command default to using all lines.

  Here's a simple word-counting alias which uses this technique to count the words in all lines by default...

      	alias wcw {
      	 local w=0
      	 !(%)% s/\w\+/let w=w+1/gx
      	 calc w
      	}

Execute a particular command separately for each line in a range
  The :g command does this, but only for the lines which contain a given regular expression. You can trick it into executing the command for every line by making it look for something that every line has. Since every line has a beginning, you can use :g/^/command to execute the command for every line.

  Note that the :g command can be used with an address range. This is often convenient.

  Here's an alias which uses this technique to search for the longest line (assuming all characters are of equal width -- no tabs or control characters)...

      	alias widest {
      	 local w=0 l
      	 !%g/^/ {
      	  if strlen(line()) > w
      	  then let w = strlen(line())
      	  then let l = current("line")
      	 }
      	 calc "Line" l "is the longest, at" w "characters."
      	}

Execute a command for each line in a particular type of region
  This is similar to the above "Execute a command for each line in a range" topic. The only difference is, we want to add a test to see if the current line is part of the desired region. Here's an alias named "inregion" which does this:

      	alias inregion {
      	  normal mz
      	  !%g/^/ {
      	    if current("region") == "!1"
      	    then !2*
      	  }
      	  normal `z
      	}

  And here's an example of how to use it. This example converts any lines in a "mixed" region to uppercase.

      	:inregion mixed s/.*/\U&/

Convert plain text to HTML source
  Other than the obvious (a long series of manual edit commands), there are two ways that you can convert text to HTML in Elvis.

  The most straightforward method is to build an alias which performs a series of substitutions. The problem with this method is that it must be rewritten for each type of input text. Here's an example of a fairly simple alias that converts plain text to HTML. (There is a more powerful version of :makehtml in the standard distribution's elvis.ali file.)

      	alias makehtml {
      	 "Convert plain text to HTML
      	 local report=0
      	 "
      	 "Protect characters which are special to HTML
      	 try !(%)%s/&/\&amp;/g
      	 try !(%)%s/</\&lt;/g
      	 try !(%)%s/>/\&gt;/g
      	 "
      	 "Convert blank lines to <p> tags
      	 try !(%)s/^$/<p>/
      	 "
      	 "If converting the whole file, then add <html>...</html>
      	 if "!%" == ""
      	 then {
      	  $a </body></html>
      	  1i <html><body>
      	 }
      	}

  The other way is simpler and more versatile, though it does require the use of an external file. It uses the :lpr command with lptype=html. Since Elvis' print mechanism supports all of Elvis' display modes, you can use this technique to convert any type of text (or even a hex dump of a binary file) into HTML. The main disadvantage of this method is, the resulting HTML is rendered exactly as it looks on the screen -- so plain text basically just has <pre> and </pre> wrapped around it, nothing else.

      	:set lptype=html lplines=0 nolpheader
      	:lp foo.html

Add new text around highlighted text, via a macro.
  The main trick is to use the visual c command to change the highlighted text, and then use `^P` as part of the replacement text. While typing the replacement text, `^P` causes a copy of the original text to be inserted. So, for example, the following macro could be used to add HTML <strong> and </strong> tags around the highlighted text.

      	:map select B c<strong>^P</strong>^[

  (Note: When typing that :map command into Elvis, you'll need to type <Ctrl-V><Ctrl-P> to get the `^P`, and <Ctrl-V><Esc> to get the `^[` character.)
Display the size of a window when it is resized
  You can use the :au OptChanged command to detect when the lines or columns options change, and display a message showing the new values.

      	:au OptChanged lines,columns message (columns)x(lines)

## C.8 Contacts

Request technical support
  The best way to get technical support is by posting a question on the comp.editors newsgroup. Be sure to mention "Elvis" in the subject line, and try to include a succinct description of the problem there, too. In the body of the message, be sure to mention the version of Elvis you're using (as reported by "`elvis --version`"), and your operating system.
Inform the authors about a bug
  Bugs should be reported via e-mail. You may not always receive prompt confirmation, but your bug reports are appreciated, and acted-upon. For OS-specific bugs, you should contact the person who ported Elvis to your operating system; the author's names and e-mail addresses are listed in the Operating Systems chapter.

  For general bug reports, you should contact the primary author, Steve Kirkendall, at kirkenda@cs.pdx.edu.

  Either way, be sure to mention the version of Elvis you're using (as reported by "elvis --version"), and your operating system.

Suggest a new feature
  Contact the authors as though you were reporting a bug. See above.
Get the latest version of Elvis
  See the "Information via the Web" section of the Tips chapter. It has links to various Elvis-related sites.