[SOLVED] Is there a fast way to exit the debugger in MIT Scheme's REPL?

Is there a fast way to exit the debugger in MIT Scheme's REPL?

Suppose I try to use an undefined variable in MIT Scheme's REPL:

1 ]=> blablabla

;Unbound variable: blablabla
;To continue, call RESTART with an option number:
; (RESTART 3) => Specify a value to use instead of blablabla.
; (RESTART 2) => Define blablabla to a given value.
; (RESTART 1) => Return to read-eval-print level 1.

2 error>

This automatically brings me into the debugger. To exit the debugger, I have to type (restart 1). Is there an alternative way that does not involve typing 11 characters just to exit the debugger? It's a bit silly that all three options involve typing 11 characters.

Solution

According to Flux's answer, pressing CTRLC twice will work with mit-scheme, but not when it runs within rlwrap

In order to make rlwrap more "transparent" with regard to CTRLC and CTRLG

Use the -W (--polling) option: rlwrap -W will make rlwrap wake up every 40 msecs to check whether the client has changed its terminal settings (in your case, its interrupt character)
Add a few lines to your .inputrc:

$if mit-scheme
  "\C-c" rlwrap-direct-keypress
  "\C-g" rlwrap-direct-keypress
$endif

Those lines will tell rlwrap (when wrapping mit-scheme) to pass on CTRLC and CTRLG even when in the middle of a line edit.

With those two tweaks, I can't tell the difference anymore in interrupt behaviour between rlwrapped and unwrapped mit-scheme

-W needs rlwrap >= 0.41, rlwrap-direct-keypress >= 0.43

For a more in-depth explanation why this works (and why the options and .inputrc entries are necessary) see this rlwrap issue on Github.