The c4 editor is an editor inspired by, and similar to, a stripped-down version of VI.
Enable the editor using #define EDITOR (editor.c)
There are 4 modes in the editor:
- NORMAL
- INSERT
- REPLACE
- COMMAND
| Key | Action |
|---|---|
| [ctrl]+a | Insert tag: COMPILE |
| [ctrl]+b | Insert tag: DEFINE |
| [ctrl]+c | Insert tag: INTERP |
| [ctrl]+d | Insert tag: COMMENT |
| [ctrl]+e | Execute the current line |
| [ctrl]+h | Left 1 char |
| [ctrl]+i | Right 8 chars (also [tab]) |
| [ctrl]+j | Down 1 line |
| [ctrl]+k | Up 1 line |
| [ctrl]+l | Right 1 char |
| [ctrl]+q | Left 8 chars |
| [ctrl]+s | Save the block to disk |
| [ctrl]+x | Delete the char under the cursor |
| [ctrl]+z | Delete the char to the left of the cursor |
| [esc-esc] | Goto NORMAL mode |
The movement keys are similar to those in VI:
| Key | Action |
|---|---|
| h | Left 1 char |
| j | Down 1 line |
| k | Up 1 line |
| l | Right 1 char |
| $ | Goto the end of the line |
| _ | Goto the beginning of the line |
| [CR] | Goto the beginning of the next line |
| [SP] | Right 1 char |
| 1 | Set tag: COMPILE |
| 2 | Set tag: DEFINE |
| 3 | Set tag: INTERP |
| 4 | Set tag: COMMENT |
| : | Change to COMMAND mode |
| + | Save the current block and goto the next block |
| - | Save the current block and goto the previous block |
| # | Redraw the screen |
| a | Append: move right 1 char and change to INSERT mode (same as 'li') |
| A | Append: goto the end of the line and change to INSERT mode (same as '$i') |
| b | Insert a BLANK/SPACE into the current line |
| B | Insert a BLANK/SPACE to the end of the block |
| c | Delete the current char and change to INSERT mode (same as 'xi') |
| C | Delete to the end of the line and change to INSERT mode (same as 'd$i') |
| d. | Delete the char under the cursor (same as 'x') |
| d$ | Delete to the end of the line |
| dd | Copy the current line into the YANK buffer and delete the line |
| dw | Delete the current word |
| D | Delete to the end of the line (same as 'd$') |
| g | Goto the top-left of the screen |
| G | Goto the bottom-left of the screen |
| i | Insert: change to INSERT mode |
| I | Insert: goto the beginning of the line and change to INSERT mode (same as '_i') |
| J | Join the current and next lines together |
| n | Insert a 'new-line' (#10/$0A) into the block |
| o | Insert an empty line BELOW the current line and change to INSERT mode |
| O | Insert an empty line ABOVE the current line and change to INSERT mode |
| p | Paste the YANK buffer into a new line BELOW the current line |
| P | Paste the YANK buffer into a new line ABOVE the current line |
| q | Right 8 chars |
| Q | Left 8 chars |
| r | Replace the char under the cursor with the next key pressed (if printable) |
| R | Change to REPLACE mode |
| t | Transfer current block to text file 'block-NNN.fth' |
| T | Transfer text file 'block-NNN.fth' to current block |
| x | Delete the char under the cursor to the end of the line |
| X | Delete the char under the cursor to the end of the block |
| Y | Copy the current line into the YANK buffer |
| z | Delete the char to the left of the cursor (same as 'hx') |
In INSERT mode, all printable characters are inserted into the block.
Carriage-Return inserts a new line.
In REPLACE mode, all printable characters are placed into the block.
Carriage-Return moves to the beginning of the next line.
COMMAND mode is invoked when pressing ':' in NORMAL mode.
| Command | Action |
|---|---|
| rl | ReLoad: discard all changes and reload the current block |
| w | Write the current block if it has changed |
| w! | Write the current block, even if it has NOT changed |
| wq | Write the current block and quit (same as ':w' ':q') |
| q | Quit, if the current block has NOT changed |
| q! | Quit, even if the current block has changed |
| ![any] | Send [any] to the c4 outer interpreter |