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0 pointsgregwebs10y ago0 comments

Yes. In Haskell you use `killThread` which throws an asynchronous exception to the thread. It is certainly difficult to perfectly cleanup resources in the face of asynchronous exceptions. However, once there are functions available to help you with this (e.g. use a bracket function whenever using resources) it becomes tractable.

This functionality is critical to being able to timeout a thread.

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masklinn10y ago

AFAIK combining killThread and bracket (or just about anything really) is fraught with issues[0] and hardly qualifies as clean.

[0] http://blog.haskell-exists.com/yuras/posts/handling-async-ex...

gregwebsOP10y ago

Yes, there is still an issue with async exceptions when there is an exception during the cleanup handler of bracket. Probably this has not received the attention it deserves because fundamentally if a cleanup handler throws an exception you may well still have resource issues. But the article also proposes ways of solving this issue, so lets not give up on async exceptions.

j / k navigate · click thread line to collapse