th-context: Test instance context

[ bsd3, library, template-haskell ] [ Propose Tags ]

Use these functions to decide an a not-quite naive fashion whether an instance already exists that satisfies a given context. This can be used to decide whether an instance needs to be generated, as in th-reify-many. Known limitation: the instances inserted into the InstMap are not fully recognized when computing the context.

Versions [faq] 0.13, 0.20, 0.20.1, 0.22, 0.23, 0.24
Dependencies base (>=4.8 && <5), containers, data-default, haskell-src-exts, lens, mtl, mtl-unleashed (>=0.5), syb, template-haskell (>=2.10), th-desugar, th-orphans (>=0.10.0), th-typegraph (>=0.31) [details]
License BSD-3-Clause
Copyright (c) David Fox
Author David Fox
Maintainer David Fox <>
Category Template Haskell
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Source repo head: git clone git://
Uploaded by DavidFox at Wed Nov 11 19:50:24 UTC 2015
Distributions NixOS:0.24
Downloads 1864 total (82 in the last 30 days)
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Status Hackage Matrix CI
Docs not available [build log]
All reported builds failed as of 2016-11-30 [all 4 reports]


  • Language
    • Haskell
      • TH
        • Language.Haskell.TH.Context


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