                  Full-Screen Editor for DX-FORTH
                  -------------------------------

Important:

After editing each screen, Ctrl-K must be pressed to UPDATE the changes.
This is a safeguard as there is no backup copy of the source file being
editing.  Until Ctrl-K is pressed, the screen may be restored to its
previous state using Ctrl-L.


Installation:

To install the editor, enter the following:

   C> FORTH  EDITOR[.SCR]

   1 LOAD

After loading, save a new version of Forth e.g. SAVE FORTHED


General screen commands:

 EDIT  ( ? -- )

   Enter the full screen editor, selecting screen ? for editing.  If
   no screen number is specified, then the screen last LISTed is used
   or, in the case a LOAD error, the screen and position where the
   error occured.

   Note: If the screen number is out of range, then the highest screen
   available is used.  If the size of the screen file was zero when
   EDIT was called, it will be extended by one block.

 L  ( -- )          List

   Lists the current screen.  The screen number is obtained from the
   variable SCR which is set by LIST, EDIT or when a LOAD error occurs.

 N  ( -- )          Next

   Increment the screen number in variable SCR then list it.

 B  ( -- )          Back

   Decrement the screen number in variable SCR then list it.


Editor commands:

1. Cursor movement

Ctrl-E   Move cursor up
Ctrl-X   Move cursor down
Ctrl-D   Move cursor right
Ctrl-S   Move cursor left
Ctrl-I   Move cursor 4 places to the right (TAB)
Ctrl-Q   Move cursor to the upper left of the screen

2. Editing

Ctrl-G   Delete character to the right of the cursor
Ctrl-H   Delete character to the left of the cursor
Ctrl-T   Erase all characters to the right of the cursor
Ctrl-O   Insert space at the current cursor position
Ctrl-Y   Delete the current line. Lines below cursor are moved up one
         position. Pop a line from circular buffer into the bottom line
Ctrl-N   Insert blank line. Lines below cursor are moved down one
         position. Push bottom line to the circular buffer
Ctrl-W   Split the current line at the cursor position
Ctrl-F   Join the next line at the cursor position
Ctrl-A   Copy the contents of the current line to the one-line buffer
Ctrl-P   Copy the contents of the one-line buffer to the current line
Ctrl-K   Update all changes made to the screen

3. Miscellaneous

Ctrl-C   Move to the next screen
Ctrl-R   Move to the previous screen
Ctrl-J   Jump to another screen
Ctrl-B   Redraw the screen
Ctrl-L   Reload the current file block
Ctrl-V   Toggle between insert or overwrite mode
Ctrl-U   Exit the editor
Ctrl-Z   Multi-function command
         S - clear the screen contents
         B - clear the circular buffer contents
         I - insert a blank screen at the current position
         D - delete the current screen copying it to the buffer
ESC      Toggle between normal and graphics mode

4. Utilities

The following commands are available from the EDITOR vocabulary.

 IMPORT  ( n1 n2 -- )

   Copy screens n1 thru n2 from the secondary file inserting them
   beginning at screen SCR of the current file.

 EXPORT  ( n1 n2 -- )

   Copy screens n1 thru n2 from the current file inserting them
   beginning at screen SCR of the secondary file.

IMPORT and EXPORT assume two screen files are currently open and SCR
of the target file has been set (SCR may be viewed with MAP).  After
the operation, target SCR is set to the last block written plus 1.

5. Notes

In the IBM-PC version of the editor, the arrows keys, PgUp, PgDn, Home,
Insert and Delete keys may be used in addition to the usual control-key
sequences.

COPY COPIES EXPAND (found in earlier versions of the editor) are redundant
as the ability to insert or delete screens is now available from Ctrl-Z.

To extend a screenfile, enter EDIT then jump to the desired screen number
using Ctrl-J.  Alternatively, truncating/extending a screenfile may also
be done from the Forth environment using FILEBLOCKS.

A special graphics mode has been added.  It is toggled via the ESC key
and allows graphic characters to be entered from the keyboard.  It is
intended to allow the insertion of PC symbols or graphic characters into
quoted strings.  Refer to DX-FORTH.TXT for a table of keys and their
corresponding codes.  To exit graphics mode, press ESC again.

The WHERE command has been removed as its function is now incorporated
in EDIT.
