^C / Ctrl-C closes REPL expression interpreter interactive loop

bjornregnell · March 10, 2021, 12:13pm

I’ve just made an issue here on the coming new Scala 3 REPL:

github.com/lampepfl/dotty-feature-requests

Make REPL handle interrupt of running code without killing its process (like in Ammonite)

opened 12:10PM - 10 Mar 21 UTC

closed 08:10AM - 05 Jun 23 UTC

It would be great if the REPL could interrupt running code without loosing the c…urrent session. Currently on linux: ``` sbt> scalaVersion [info] 3.0.0-RC2-bin-20210308-0dbe970-NIGHTLY sbt> consoleQuick scala> while true do () <<interrupted with SIGINT>> [warn] Canceling execution... [warn] Run canceled. Cancelled: consoleQuick [error] Cancelled: consoleQuick [error] Use 'last' for the full log. sbt> ``` Ammonite solves this (perhaps through `sun.misc.Signal`: https://ammonite.io/#Interruptingrun-awayexecutionwithCtrl-C ``` @ while(true) () ... hangs ... ^Ctrl-C Interrupted! @ ``` From Ammonite docs: "The traditional Scala REPL doesn't handle runaway code, and gives you no option but to kill the process, losing all your work. Ammonite-REPL lets you interrupt the thread, stop the runaway-command and keep going." See also discussion here: https://users.scala-lang.org/t/c-ctrl-c-closes-repl-expression-interpreter-interactive-loop/7187/8

Also @tomoyo255 it struck me that sbt seems to handle SIGINT so at least you don’t loose your sbt session as you can see in the issue example.