Dead simple line editor
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It supports the bare minimum you would expect:
- Backspace to delete text
- Left and right arrow keys to move cursor
- Inserting and deliting text in the middle of input
- Callback mapping to the Tab key that can arbitrarily
modify the line to for example support autocomplete
The interface is simple.
char *in = readln(prompt, tabfunc);
enters the editor with the given prompt. the funciton
returns once the user hits the enter key (or othwise
inserts a newline), returning a null-terminated string.
Other ANSI escape codes than the arrow keys are not
supported yet. For example, Delete, Home, End & Co
are not supported and will cause the reader to exit,
as will the function keys F1, F2 etc.
Modifying the ANSI escape code recognition to use a
state machine (Lex) might allow supporting this more
easily, but at the moment hard coding parsing every
useful escape code in a tree of if-else and switch
statements is just too tedious.