1

I'd like to run a series of tasks but stop should any of them fail, hence I've written (something like):

for task in [TASKS]; do
  process "$task" || break
  commit "$task"
done

This works fine, but (as specified) the exit status of this loop is zero even if we break early. Ideally break-ing would be able to convey the failure.

I know returning 0 is the documented behavior of break, but I'm curious if there are any relatively clean workarounds. The best I can imagine is wrapping this in a function and setting a didBreak variable, and using that as the exit status (of the function). It'd work, but it feels overly-complex.

1

You could do something like

for t in $tasks; do
  process "$t" || { failed=1; break; }
  commit "$t"
done

if (( failed )); then
   echo "Failed something" >&2
fi
  • Yeah, that's pretty much what I'm envisioning (aside from wrapping it in a function), but it feels kludgy to me. Maybe that's the best I can do, though. – dimo414 Jan 27 '17 at 22:24
  • @dimo414 Doesn't feel too kludgy to me. You could even use failed="$t" or something to later be able to tell what task it was that failed. – Kusalananda Jan 27 '17 at 22:27
  • process prints enough information to describe what went wrong; all that's missing is stopping after the loop terminates-early. You're right it's not that bad, I just don't love the separation. – dimo414 Jan 27 '17 at 23:26
0

My imagined solution is:

run_til_failure() {
  local didBreak=0
  for task in [TASKS]; do
    process "$task" || { didBreak=1; break; }
    commit "$task"
  done
  local loopExit=$?
  if (( loopExit )); then return $loopExit; fi
  return $didBreak
}

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