Impliments a modal vi-style editor, with only hjkl movement keys, plus a q quit command, in 150 lines of basic C++. I suppose the ANSI escapes are arcane, but they always are. When I say minimal, I mean it; there is no saving or loading, and no scrolling, dealing with long lines, or exiting cleanly. This is more of an example of how simple the core of a text editor can be, rather than a polished and usable product, and of course a good opertunity to dabble in C++.
While it may not be performant on massive text files, for most source-code-sized inputs, the strategy of simply moving the entire text buffer for every character is perfectly workable on a modern computer, and much simpler to code.
To be clear, the commands are:
| Mode | Key | Action |
|---|---|---|
| Insert | Backspace | Delete the character to the left of the cursor |
| Insert | Escape | Switch to command mode |
| Command | h | Move left |
| Command | j | Move up |
| Command | k | Move down |
| Command | l | Move right |
| Command | i | Switch to insert mode |
| Command | q | Quit the program |