📄 Edu - The new Euphoria Editor


 This page describes the Euphoria editor "ed". When you download Lib2 from the
 Download page it comes with an advanced editor, "edu", which is based on "ed".

 "edu" editor includes more menu commands, full screen editing, full screen
 lists, and on Linux system you can run it in UTF-8 mode by adding "-u" in the
 command line:

       edu -u filename


 edu includes also the following special keys:

 control-K       - display help for the current keyword (where the cursor is)

 control-W       - start/stop recording a macro

 control-O       - run a recorded macro

 control-F       - freeze/unfreeze the cursor (for writing a string in RTL mode)


 You should install Lib2 version 1.22 or later to use "edu" editor
 version 2.30. More details about the "edu" editor are in the source file
 itself, "edu.ex".

 If you are running Euphoria 3.1.1 on Windows-10, then you should install Lib2
 version 1.24 or later, and run "edu" editor with eduw.bat (not with edu.bat).

 Note that on Windows-10 you should run "ed" using exwc.exe or exw.exe
 (not with ex.exe).

📄 Ed - The Euphoria Editor


 Introduction
 ------------

 The Euphoria download package includes a handy, text-mode editor, ed, that's
 written completely in Euphoria. Many people find ed convenient for editing
 Euphoria programs and other files, but there is no requirement that you use
 it.

 If you don't like ed, you have many alternatives. David Cuny's EE editor is a
 DOS-based editor for Euphoria that's also written in Euphoria. It has a
 friendly mouse-based user interface with drop down menus etc. It's available
 from the RDS Web site. There are several other Euphoria-oriented editors that
 run on DOS, Windows, Linux and FreeBSD. Check the Editors section of our
 Archive. In fact, any text editor can be used to edit a Euphoria program,
 including DOS Edit or Windows NotePad.

 Summary
 -------


 usage 1:  ed filename
 usage 2:  ed

 After any error, just type "ed", and you'll be placed in the editor, at the
 line and column where the error was detected. The error message will be at the
 top of your screen.

 Euphoria-related files are displayed in color. Other text files are in mono.
 You'll know that you have misspelled something when the color does not change
 as you expect. Keywords are blue. Names of routines that are built in to the
 interpreter appear in magenta. Strings are green, comments are red, most other
 text is black. Balanced brackets (on the same line) have the same color. You
 can change these colors as well as several other parameters of ed. See
 "user-modifiable parameters" near the top of ed.ex.

 The arrow keys move the cursor left, right, up or down. Most other characters
 are immediately inserted into the file.

 In Windows, you can "associate" various types of files with ed.bat. You will
 then be put into ed when you double-click on these types of files - e.g. .e,
 .pro, .doc etc. Main Euphoria files ending in .ex (.exw) might better be
 associated with "ex.exe" ("exw.exe").

 ed is a multi-file/multi-window DOS editor. Esc c will split your screen so
 you can view and edit up to 10 files simultaneously, with cutting and pasting
 between them. You can also use multiple edit windows to view and edit
 different parts of a single file.

 Special Keys
 ------------

 Some PC keys do not work in a Linux or FreeBSD text console, or in Telnet, and
 some keys do not work in an xterm under X windows. Alternate keys have been
 provided. In some cases on Linux/FreeBSD you might have to edit ed.ex to map
 the desired key to the desired function.

 Delete            - Delete the current character above the cursor.

 Backspace         - Move the cursor to the left and delete a character.

 control-Delete    - Delete the current line. (control-Delete is not available
                     on all systems.)

 control-d         - Delete the current line. (same as control-Delete)

 Insert            - Re-insert the preceding series of Deletes or
                     control-Deletes before the current character or current
                     line.

 control-arrow-left    - Move to the start of the previous word. On
                         Linux/FreeBSD use control-L.

 control-arrow-right   - Move to the start of the next word. On Linux/FreeBSD
                         use control-R.

 Home              - Move to the beginning of the current line.

 End               - Move to the end of the current line.

 control-Home      - Move to the beginning of the file. This works with ex.exe
                     only. On Windows/Linux/FreeBSD use control-T (i.e. Top)

 control-End       - Move to the end of the file. This works with ex.exe only.
                     On Windows/Linux/FreeBSD use control-B, (i.e. Bottom)

 Page Up           - Move up one screen. In a Linux/FreeBSD xterm use control-U

 Page Down         - Move down one screen. In a Linux/FreeBSD xterm use
                     control-P

 F1 ... F10        - Select a new current window. The windows are numbered from
                     top to bottom, with the top window on the screen being F1.

 F12               - This is a special customizable command. It is set up to
                     insert a Euphoria comment mark "--" at the start of the
                     current line. You can easily change it to perform any
                     series of key strokes that you like, simply by redefining
                     constant CUSTOM_KEYSTROKES near the top of ed.ex.



 Escape Commands
 ---------------

 Press and release the Esc key, then press one of the following keys:

 h   - Get help text for the editor, or Euphoria. The screen is split so you
       can view your program and the help text at the same time.

 c   - "Clone" the current window, i.e. make a new edit window that is
       initially viewing the same file at the same position as the current
       window. The sizes of all windows are adjusted to make room for the new
       window. You might want to use Esc l to get more lines on the screen.
       Each window that you create can be scrolled independently and each has
       its own menu bar. The changes that you make to a file will initially
       appear only in the current window. When you press an F-key to select a
       new window, any changes will appear there as well. You can use Esc n to
       read a new file into any window.

 q   - Quit (delete) the current window and leave the editor if there are no
       more windows. You'll be warned if this is the last window used for
       editing a modified file. Any remaining windows are given more space.

 s   - Save the file being edited in the current window, then quit the current
       window as Esc q above.

 w   - Save the file but do not quit the window.

 e   - Save the file, and then execute it with ex, exw or exu. When the program
       finishes execution you'll hear a beep. Hit Enter to return to the
       editor. This operation may not work if you are very low on extended
       memory. You can't supply any command-line arguments to the program.

 d   - Run an operating system command. After the beep, hit Enter to return to
       the editor. You could also use this command to edit another file and
       then return, but Esc c is probably more convenient.

 n   - Start editing a new file in the current window. Deleted lines/chars and
       search strings are available for use in the new file. You must type in
       the path to the new file. Alternatively, you can drag a file name from a
       Windows file manager window into the MS-DOS window for ed. This will
       type the full path for you.

 f   - Find the next occurrence of a string in the current window. When you
       type in a new string there is an option to "match case" or not. Press y
       if you require upper/lower case to match. Keep hitting Enter to find
       subsequent occurrences. Any other key stops the search. To search from
       the beginning, press control-Home before Esc f. The default string to
       search for, if you don't type anything, is shown in double quotes.

 r   - Globally replace one string by another. Operates like Esc f command.
       Keep hitting Enter to continue replacing. Be careful -- there is no way
       to skip over a possible replacement.

 l   - Change the number of lines displayed on the screen. Only certain values
       are allowed, depending on your video card. Many cards will allow 25, 28,
       43 and 50 lines.

       In a Linux/FreeBSD text console you're stuck with the number of lines
       available (usually 25). In a Linux/FreeBSD xterm window, ed will use the
       number of lines initially available when ed is started up. Changing the
       size of the window will have no effect after ed is started.

 m   - Show the modifications that you've made so far. The current edit buffer
       is saved as editbuff.tmp, and is compared with the file on disk using
       the DOS fc command, or the Linux/FreeBSD diff command. Esc m is very
       useful when you want to quit the editor, but you can't remember what
       changes you made, or whether it's ok to save them. It's also useful when
       you make an editing mistake and you want to see what the original text
       looked like.

 ddd - Move to line number ddd. e.g. Esc 1023 Enter would move to line 1023 in
       the file.

 CR  - Esc Carriage-Return, i.e. Esc Enter, will tell you the name of the
       current file, as well as the line and character position you are on, and
       whether the file has been modified since the last save. If you press Esc
       and then change your mind, it is harmless to just hit Enter so you can
       go back to editing.



 Recalling Previous Strings
 --------------------------

 The Esc n, Esc d, Esc r and Esc f commands prompt you to enter a string. You
 can recall and edit these strings just as you would at the DOS or
 Linux/FreeBSD command line. Type up-arrow or down-arrow to cycle through
 strings that you previously entered for a given command, then use left-arrow,
 right-arrow and the delete key to edit the strings. Press Enter to submit the
 string.


 Cutting and Pasting
 -------------------

 When you control-Delete (or control-D) a series of consecutive lines, or
 Delete a series of consecutive characters, you create a "kill-buffer"
 containing what you just deleted. This kill-buffer can be re-inserted by
 moving the cursor and then pressing Insert.

 A new kill-buffer is started, and the old buffer is lost, each time you move
 away and start deleting somewhere else. For example, cut a series of *lines*
 with control-Delete. Then move the cursor to where you want to paste the lines
 and press Insert. If you want to copy the lines, without destroying the
 original text, first control-Delete them, then immediately press Insert to
 re-insert them. Then move somewhere else and press Insert to insert them
 again, as many times as you like. You can also Delete a series of individual
 *characters*, move the cursor, and then paste the deleted characters somewhere
 else. Immediately press Insert after deleting if you want to copy without
 removing the original characters.

 Once you have a kill-buffer, you can type Esc n to read in a new file, or you
 can press an F-key to select a new edit window. You can then insert your
 kill-buffer.


 Use of Tabs
 -----------

 The standard tab width is 8 spaces. The editor assumes tab=8 for most files.
 However, it is more convenient when editing a program for a tab to equal the
 amount of space that you like to indent. Therefore you will find that tabs are
 set to 4 when you edit Euphoria files (or .c, or .h or .bas files). The editor
 converts from tab=8 to tab=4 when reading your program file, and converts back
 to tab=8 when you save the file. Thus your file remains compatible with the
 tab=8 world, e.g. MS-DOS PRINT, EDIT, etc. If you would like to choose a
 different number of spaces to indent, change the line at the top of ed.ex that
 says "constant PROG_INDENT = 4".


 Long Lines
 ----------

 Lines that extend beyond the right edge of the screen are marked with an
 inverse video character in the 80th column. This warns you that there is more
 text "out there" that you can't see. You can move the cursor beyond the 80th
 column. The screen will scroll left or right so the cursor position is always
 visible.


 Maximum File Size
 -----------------

 Like any Euphoria program, ed can access all the memory on your machine. It
 can edit huge files, and unless disk swapping occurs, most operations will be
 very fast.


 Non-text Files
 --------------

 ed is designed for editing pure text files, although you can use it to view
 other files. As ed reads in a file, it replaces certain non-printable
 characters (less than ASCII 14) with ASCII 254 - small square. If you try to
 save a non-text file you will be warned about this. (MS-DOS Edit will quietly
 corrupt a non-text file - do not save!). Since ed opens all files as "text"
 files, a control-z character (26) embedded in a file will appear to ed to be
 the end of the file.


 Long Filenames
 --------------

 Although ed is a DOS editor, you can edit existing files that have pathnames
 with long names in them, and the full file name will be preserved. However in
 this release ed will not create *new* files with long names. The name will be
 truncated to the standard DOS 8.3 length. (but see Platform below)


 Line Terminator
 ---------------

 The end-of-line terminator on Linux/FreeBSD is simply \n. On DOS and Windows,
 text files have lines ending with \r\n. If you copy a DOS or Windows file to
 Linux/FreeBSD and try to modify it, ed will give you a choice of either
 keeping the \r\n terminators, or saving the file with \n terminators.


 Source Code
 -----------

 The complete source code to this editor is in bin\ed.ex and bin\syncolor.e.
 You are welcome to make improvements. There is a section at the top of ed.ex
 containing "user-modifiable" configuration parameters that you can adjust. The
 colors and the cursor size may need adjusting for some operating environments.



 Platform
 --------

 euphoria\bin\ed.bat can be set up to run ed.ex using exwc.exe or ex.exe. You
 are better off running ed with ex.exe on Windows 95/98/ME. You'll get much
 quicker screen updates than with exwc.exe. On Windows XP you'll be a bit
 better off using exwc.exe. You'll get slightly quicker screen updates, and
 you'll be able to create files with long names, not just open existing ones.
 However some special keys won't work with exwc.exe, e.g. you'll have to use
 control-t and control-b instead of control-Home and control-End. On Linux and
 FreeBSD there are no problems with long filenames, and the keyboard response
 is always fast.