@args --debugger --option debugger-on-warn true
Enter debugger with debugger-on-warn set.
  nix-repl> let inspect = v: builtins.warn "inspect is deprecated" (throw "this happens after"); in inspect { }
  warning: inspect is deprecated
  warning: builtins.warn reached

Continuing after the warn then breaks on the `throw`
  nix-repl> :c
  error: this happens after

Finally, continuing after that error exits and prints the error
  nix-repl> :c
  error: this happens after