Derefing a future hangs

[vemv]

I have a fix.clj with the following contents:

(require '[dev.formatting.fix])

@(dev.formatting.fix/fix!)

Where @ is used to wait on a future.

lein exec -p scripts/formatting/fix.clj hangs forever. If I run the same exact code in lein repl, it won't.

What could it be going on here?

Cheers - Victor

[vemv]

Workaround: adding (System/exit 0) at the end of the script

[kumarshantanu]

@vemv Could you try adding (shutdown-agents) instead? It's likely that the script is blocked because the thread pool is still active with non-daemon threads.

[vemv]

Tried out!

Unfortunately it didn't work:

(println :a)
(shutdown-agents)
(println :b)

This prints :a, :b then hangs forever.

This doesn't happen in a project created from scratch. But in a real production project there are too many dependencies to determine the culprit.

Perhaps the simplest thing would be to recommend (System/exit 0) in the README.

Cheers - Victor

[kumarshantanu]

I'm not sure what the problem could be - does the code you call launch a thread-pool that you are not shutting down in your script? When I execute future in a simple script I am unable to reproduce the problem. Do you have a minimal standalone script that can reproduce the issue?