A Prelude inspired by the Elm programming language

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Stackage Nightly 2022-02-07:
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BSD-3-Clause licensed by NoRedInk
Maintained by [email protected]
This version can be pinned in stack with:nri-prelude-,4517


A Prelude inspired by the Elm programming language.

This package re-implements API’s and re-uses documentation from elm-core (license) and elm-test (license).


Breaking changs:

  • Test.fromTestTree has been removed.
  • Fuzz.Fuzzer is now an opague type and no a synonomy for Hedgehog.Gen.
  • Expect.Task.TestFailure renamed to Expect.Task.failure.
  • Test.Runner.Tasy.main renamed to


  • Test reports now show source locations of failing tests.
  • Fuzz module has been extended and now covers almost the entire API of its Elm counterpart.
  • Dependency on tasty has been dropped.

  • Breaking change: drop Platform.TracingSpan constructor.
  • Add Platform.emptyTracingSpan export.
  • Relax version bounds to encompas tasty-1.4.

  • Relax version bounds to encompass time-1.11.

  • Fix tests to allow inclusion in stackage.

  • Relax version bounds to encompass pretty-diff- and base-

  • Relax version bounds to be compatible with bytestring-0.11.

  • Initial release.