Criterion measurement functionality and associated types

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Stackage Nightly 2024-07-22:
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BSD-3-Clause licensed by Bryan O'Sullivan
Maintained by Marco Zocca <zocca.marco gmail>, Ryan Scott
This version can be pinned in stack with:criterion-measurement-,2070

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Measurement-related functionality extracted from Criterion, with minimal dependencies. The rationale for this is to enable alternative analysis front-ends.


  • Ensure that Criterion.Measurement.Types.Internal is always compiled with optimizations, even if the criterion-measurement library itself happens to be built with -O0 or -fprof-auto. This is necessary to ensure that the inner benchmarking loop of criterion always finishes in a timely manner, even if the rest of the library is not fully optimized.

  • Add nfAppIO and whnfAppIO functions, which take a function and its argument separately like nf/whnf, but whose function returns IO like nfIO/whnfIO. This is useful for benchmarking functions in which the bulk of the work is not bound by IO, but by pure computations that might otherwise be optimized away if the argument is known statically.

  • This is the first release of criterion-measurement. The changelog notes below are copied from the notes for the corresponding criterion release, criterion-

  • Move the measurement functionality of criterion into a standalone package, criterion-measurement. In particular, cbits/ and Criterion.Measurement are now in criterion-measurement, along with the relevant definitions of Criterion.Types and Criterion.Types.Internal (both of which are now under the Criterion.Measurement.* namespace). Consequently, criterion now depends on criterion-measurement.

    This will let other libraries (e.g. alternative statistical analysis front-ends) to import the measurement functionality alone as a lightweight dependency.

  • Fix a bug on macOS and Windows where using runAndAnalyse and other lower-level benchmarking functions would result in an infinite loop.