1.4.1 -- 2025-08-05

• Build with GHC 9.12

1.4.0 -- 2023-03-26

• Build with GHC 9.6
• Build with free-5.2
• Remove instances for ListT, as this type is deprecated and removed from transformers-0.6.
• Remove instances for ErrorT, as this type is deprecated and removed from transformers-0.6.

1.3.13 -- 2022-02-20

Other changes

• Increased the upper-bound of time to < 1.13.
• Increased the upper-bound of base to < 4.17.
• Increased the upper-bound of semigroups to < 0.21.

1.3.12 -- 2020-12-14

Other changes

• Increase the upper-bound of time to < 1.12.
• Increase the upper-bound of prettyprinter to < 1.8.

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1.3.11 -- 2020-08-18

Other changes

• Increase the lower-bound of unliftio-core to 0.2.0.0

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1.3.10 -- 2020-06-17

Other changes

• Add MonadUnliftIO instance to DiscardLoggingT
• Support base-4.14

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1.3.9 -- 2020-01-25

Other Changes

• Support prettyprinter-1.6

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1.3.8 -- 2019-11-10

Other Changes

• Support prettyprinter-1.5

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1.3.7 -- 2019-10-22

Other Changes

• Support prettyprinter-1.4

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1.3.6 -- 2019-09-19

New

• Added MonadFail instances.

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1.3.5 -- 2019-09-17

Other Changes

• Support base-4.13
• Support GHC 8.8.1
• Support prettyprinter-1.3

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1.3.4 -- 2019-05-15

Other Changes

• Support semigroups-0.19.

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1.3.3 -- 2018-09-30

Other Changes

• Support stm-2.5.
• Support base-4.12.

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1.3.2 -- 2018-07-06

Other Changes

• Support free-5.1.

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1.3.1

• Add MonadUnliftIO instance for LoggingT.

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1.3.0

Major Changes

• Switch from wl-pprint-text to prettyprinter.

Other changes

• Change the type of the ribbonFrac parameter of withFDHandler from Float to Double to reflect the underlying prettyprinter API.

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1.2.6

Other Changes

• Increased upper bound of base and support GHC 8.4.

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1.2.5

Other Changes

• Increased upper bound of exceptions.

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1.2.4

Other Changes

• Increased upper bound of exceptions.

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1.2.3

Other Changes

• Increased upper of async.

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1.2.2

Other Changes

• Increased upper bound of free and time.

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1.2.1

Other Changes

• Increased upper bound of base to allow < 4.11.

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1.2.0

Major Changes

• withFDHandler now explicitly flushes the file handle whenever log entries are rendered out. Thanks to @filterfish for identifying this omission that could lead to log messages being dropped.

  Upgrade steps: no changes other than updating logging-effect.

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1.1.3

Other Changes

• Increased upper bound of time to allow < 1.9.

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1.1.2

Other changes

• Increased upper bound of time

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1.1.1

• withBatchedHandler no longer prints empty log messages. Previously, if you ran a program that didn't log but used withBatchedHandler (or anything that used that), an empty log message would be output. Thanks to @codedmart for fixing this.

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1.1.0

Breaking changes:

• MonadLog no longer has logMessage as a function. It now has logMessageFree which takes a free monoid of log messages. If you were just using logging-effect then this won't affect you, as logMessage still exists with the same signature outside the type class.

• MonadLog now comes with a law that states that logging is a monoid homomorphism. This essentially means that you have to treat all log messages uniformly.

• Pass-through instances for all "stock" monad transformers have been added (all of transformers, CatchT from exceptions and FreeT/FT from free).

• WithSeverity now has instances of Traversable and Foldable

• WithTimestamp now has instances of Eq, Ord, Read and Show.

Additions:

• A set of convenience functions have been added for quickly logging with severity. The combinators are: logDebug, logInfo, logNotice, logWarning, logError, logCritical, logAlert and logEmergency.

• mapLogMessage got a companion function mapLogMessageM that works with monadic tranformations.

Other

• Many documentation bug fixes.

• INLINEABLE pragmas added.

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1.0.0

• Initial release