slave-thread: A fundamental solution to ghost threads and silent exceptions

[ concurrency, concurrent, error-handling, exceptions, failure, library, mit ] [ Propose Tags ]

Vanilla thread management in Haskell is low level and it does not approach the problems related to thread deaths. When it's used naively the following typical problems arise:

This library solves all the issues above with a concept of a slave thread. A slave thread has the following properties:

  1. When it dies for whatever reason (exception or finishing normally) it kills all the slave threads that were forked from it. This protects you from ghost threads.

  2. It waits for all slaves to die and execute their finalizers before executing its own finalizer and getting released itself. This gives you hierarchical releasing of resources.

  3. When a slave thread dies with an uncaught exception it reraises it in the master thread. This protects you from silent exceptions and lets you be sure of getting informed if your program gets brought to an erroneous state.

Versions [RSS] [faq] 0.1.0, 0.1.1, 0.1.2, 0.1.3, 0.1.4, 0.1.5, 0.1.6,, 1.0.1,, 1.0.2,,,,,,,, 1.0.3, 1.1,
Dependencies base (>=4.9 && <5), deferred-folds (==0.9.*), focus (>=1 && <1.1), foldl (==1.*), stm-containers (>=1.1 && <1.3) [details]
License MIT
Copyright (c) 2014, Nikita Volkov
Author Nikita Volkov <>
Maintainer Nikita Volkov <>
Category Concurrency, Concurrent, Error Handling, Exceptions, Failure
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Source repo head: git clone git://
Uploaded by NikitaVolkov at 2021-05-31T11:14:11Z
Distributions NixOS:, Stackage:
Downloads 11676 total (69 in the last 30 days)
Rating 2.0 (votes: 1) [estimated by Bayesian average]
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Status Hackage Matrix CI
Docs available [build log]
All reported builds failed as of 2021-05-31 [all 1 reports]


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