Tracking patches for Monad of No Return

[L0neGamer]

In #328 we accepted the proposal to eventually remove return from Monad and mappend from Monoid. I've been making progress on the implementation here, and thought I should check how much of clc-stackage was broken.

In short, a lot of it.

The good news is I have patches for all ~148 packages that are needed to get stackage back on its feet.

The bad news is that these patches now have to be submitted to each package, reviewed, accepted, and uploaded to hackage to ensure a smooth transfer.

This is why I've made this issue: to track how many packages have had patches submitted; and to ask for help in submitting patches to all these packages (discourse post).

Here is a huge file with the vast majority of the patches; there are 24 or so not included in this file I will manage by myself (since I was doing them fully manually before a certain point): https://gist.github.com/L0neGamer/3df4008fd458030cf3cf2c374ccfa3ec

I urge those that submit patches to review them and make sure they make sense for the context of the project they are in. I did not ensure that these patches were well made or made sense for the full support window of each package, I only ensured that they worked for ghc-9.12.4 with my MONR changes.

When making your patches, bear the following tidbits in mind:

• The aim is to remove all definitions of return and mappend, and make sure all definitions of pure and (<>) don't simply refer to return and mappend
• Semigroup was introduced in base-4.9.0.0, and only became a superclass of Monoid in base-4.11.0.0. Thus patches for packages that cover that range of versions must add CPP to remove the mappend definition after base-4.11.0.0
• Applicative was introduced as a superclass of Monad in base-4.8.0.0. Thus patches for packages that cover that range of versions must add CPP to remove the return definition after base-4.8.0.0
• Ideally even canonical definitions (of return = pure and mappend = (<>)) should be removed so that in later stages we don't have more breakage
• If you do help me patch these (thank you!) let me know so I can tick an item off the list and link to the patch for further tracking

(addendum: removing canonical definitions is also a good idea as we go. for a previous search for these changes, please see rhendric's comment on the original proposal)

Packages for general patching (I'll tick when there's a release on hackage!):

• acid-state-0.16.1.4 - Remove noncanonical definitions. acid-state/acid-state#180
• alex-meta-0.3.0.13
• algebra-4.3.1
• audacity-0.0.2.2
• backtracking-0.1.0
• battleship-combinatorics-0.0.1
• bencode-0.6.1.1
• binary-search-2.0.0
• BNFC-meta-0.6.1
• board-games-0.4.0.1
• boundingboxes-0.2.3
• c2hs-0.28.8
• cgi-3001.5.1.0
• comfort-graph-0.0.4.1
• compensated-0.8.3
• constrained-categories-0.4.2.0
• control-monad-free-0.6.2
• copilot-theorem-4.7.1
• csp-1.4.0
• data-diverse-4.7.1.0
• data-inttrie-0.1.4
• data-msgpack-types-0.0.3
• djinn-lib-0.0.1.4
• dockerfile-0.2.0
• dotgen-0.4.3
• drifter-0.3.0
• drinkery-0.4
• elerea-2.9.0
• enumset-0.1
• errors-2.3.0
• essence-of-live-coding-0.2.9
• exact-pi-0.5.0.2
• expiring-cache-map-0.0.6.1
• explicit-exception-0.2
• fakedata-1.0.5
• ghcjs-perch-0.3.3.3
• gloss-rendering-1.13.2.1
• graphite-0.10.0.1
• graphviz-2999.20.2.1
• happstack-server-7.9.3
• happy-meta-0.2.1.0
• heap-1.0.4
• heist-1.1.1.2
• hformat-0.3.3.1
• histogram-fill-0.9.1.0
• hmatrix-0.20.2
• HPDF-1.8 - Draw.return: remove method implementation for compatibility with MonadOfNoReturn hsyl20/HPDF#20
• HTF-0.15.0.2
• hxt-tagsoup-9.1.4
• iconv-0.4.1.3
• invertible-0.2.0.8
• io-streams-1.5.2.2 - Remove noncanonical definitions snapframework/io-streams#96
• jmacro-0.6.18
• json-0.11
• lattices-2.2.1.1
• lazyio-0.1.0.4
• lazyppl-1.0.1
• lens-family-core-2.1.3
• libmpd-0.10.0.1
• mandrill-0.5.8.0
• matrix-static-0.3
• MemoTrie-0.6.11
• midi-0.2.2.4
• monad-chronicle-1.1.0.1 - MoNR: Remove extraneous method definitions haskellari/these#217
• monad-resumption-0.1.4.0
• monad-unlift-ref-0.2.1
• monoid-transformer-0.0.4
• multiset-0.3.4.3
• netwire-5.0.3
• nondeterminism-1.5
• non-empty-0.3.5
• non-empty-sequence-0.2.0.4
• non-negative-0.1.2
• optional-args-1.0.2
• partial-handler-1.0.3
• pathtype-0.8.1.3
• persistable-record-0.6.0.6
• pipes-concurrency-2.0.14
• pipes-fluid-0.6.0.1
• plaid-0.1.0.4
• pooled-io-0.0.2.3
• probability-0.2.8
• promises-0.3
• quickcheck-classes-base-0.6.2.0
• quickcheck-transformer-0.3.1.2
• range-set-list-0.1.4.1
• reactive-midyim-0.4.1.1
• reform-0.2.7.6
• regex-applicative-0.3.4
• rest-rewrite-0.4.5
• rio-0.1.24.0
• safe-decimal-0.2.1.0
• scanner-0.3.1
• servant-docs-0.13.1
• set-cover-0.1.1.1
• shell-conduit-5.0.0
• socks-0.6.1
• sqlite-simple-0.4.19.0
• step-function-0.2.1
• storablevector-0.2.13.2
• stringbuilder-0.5.1
• swagger2-2.9
• synthesizer-core-0.8.4
• synthesizer-dimensional-0.8.1.1
• system-filepath-0.4.14.1
• tdigest-0.3.1
• text-latin1-0.3.1
• text-printer-0.5.0.2
• text-region-0.3.1.0
• timespan-0.4.0.0
• unagi-chan-0.4.1.4
• unexceptionalio-0.5.1
• unicode-0.0.1.1
• union-find-array-0.1.0.4
• unique-logic-tf-0.5.1.1
• varying-0.8.1.0
• vinyl-0.14.3
• web-routes-0.27.16
• wl-pprint-annotated-0.1.0.1
• wl-pprint-text-1.2.0.2
• xlsx-1.2.0 - monoid of no mappend, monad of no return qrilka/xlsx#204
• xml-picklers-0.3.6
• yi-core-0.19.4
• yi-rope-0.11

Packages I plan to patch/solve somehow:

• blaze-markup - MoNR: Remove return definition of MarkupM jaspervdj/blaze-markup#71
• case-insensitive - last updated 7 years ago, deprioritised
• Earley - MoNR: removing extraneous methods and canonising Results ollef/Earley#65
• fmlist - MonR: remove mappend definitions sjoerdvisscher/fmlist#16
• generic-data - MonR: removing mappend method definitions Lysxia/generic-data#78
• Haskell-Errors-Library - MonR: move non-canonical return definitions to pure definitions Gabriella439/Haskell-Errors-Library#64
• haskell-src-exts - last updated 7 years ago, supports GHC < 9, deprioritised
• HCodecs - MonR: remove noncanoical return and canonical mappend Mokosha/HCodecs#3
• hs-asn1/data - package archived
• hs-asn1/encoding - package archived
• hs-asn1/parse - package archived
• hs-hourglass - package archived
• List - last updated 9 years ago, no repo, deprioritised
• ListTree - last updated 10 years ago, no repo, deprioritised
• MonadPrompt - last updated 12 years ago, no repo, deprioritised
• OpenGL - MonR: moving return method definition haskell-opengl/OpenGL#102
• operational - MonR: move return definitions to pure HeinrichApfelmus/operational#35
• ordered-containers - MonR: version-gate mappend definitions dmwit/ordered-containers#37
• process-extras - MonR: canonise mappend and <> for ExitCode seereason/process-extras#22
• RefSerialize - last updated 9 years ago, no repo, deprioritised
• semialign - MoNR: Remove extraneous method definitions haskellari/these#217
• Stream - last updated 12 years ago, no repo, deprioritised
• strict - MoNR: Remove extraneous method definitions haskellari/strict#50
• these - MoNR: Remove extraneous method definitions haskellari/these#217

[thielema]

On Sun, 31 May 2026, Benjamin wrote: Packages for general patching: * audacity-0.0.2.2 * battleship-combinatorics-0.0.1 * board-games-0.4.0.1 * comfort-graph-0.0.4.1 ...

many of theses packages are maintained by me I care a lot about backwards compatibility and have to see how I can adapt to missing "return" and "mappend" methods without losing compatibility with older GHC versions.

[L0neGamer]

If you add cpp that removes the return definition from base>=4.8.0.0 that will cover Monad (as return = pure was added in that version).
If you add cpp that removes Mappend from Monoid from base >=4.11.0.0 that will cover Monoid (as mappend = (<>) was added in that version).

I'm happy to help if you need more specifics, and if you do submit your own patches please let me know!

[thielema]

On Mon, 1 Jun 2026, Benjamin wrote: If you add cpp that removes the return definition from base>=4.8.0.0 that will cover Monad (as return = pure was added in that version). If you add cpp that removes Mappend from Monoid from base >=4.11.0.0 that will cover Monoid (as mappend = (<>) was added in that version). I'm happy to help if you need more specifics, and if you do submit your own patches please let me know!

I have kept all of my packages free of CPP and try to stay compatible also with alternative compilers, Hugs in the past, MicroHs today. I will prepare my own patches.

[thielema]

On Sun, 31 May 2026, Benjamin wrote: * Semigroup was introduced in base-4.9.0.0, and only became a superclass of Monoid in base-4.11.0.0

Applicative became superclass of Monad in base-4.8, aka GHC-7.10. Thus Cabal files should get according lower version bounds on `base`.

[unhammer]

looks like HPDF is patched upstream hsyl20/HPDF@7f07e08

and io-streams is patched (conditionally with CPP) snapframework/io-streams@9d519d1