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Switch from template-haskell to template-haskell-lift#661

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Lysxia merged 1 commit intohaskell:masterfrom
TeofilC:wip/th-lift
Jan 20, 2026
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Switch from template-haskell to template-haskell-lift#661
Lysxia merged 1 commit intohaskell:masterfrom
TeofilC:wip/th-lift

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@TeofilC
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@TeofilC TeofilC commented Oct 10, 2025 •
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We switch our dependency on template-haskell to a dependency on template-haskell-lift. This smaller library is more stabler and if we can remove the template-haskell dependency from all boot libraries then template-haskell will be much easier to re-install since it no longer needs to be in GHC's dependency closure.

For more information see the GHC proposal that introduced this library: ghc-proposals/ghc-proposals#696

This GHC MR tests this PR against GHC-HEAD: https://gitlab.haskell.org/ghc/ghc/-/merge_requests/14978

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Lysxia commented Dec 15, 2025

What's the status of this?

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TeofilC commented Dec 15, 2025

What's the status of this?

I'm currently waiting for GHC-9.14 to be released. And then I'll update all the PRs for boot libs.

If we want new releases of text to be backportable to older GHCs then I will need to introduce some CPP to allow building with GHC when th-lift isn't a boot lib (note that end users can build th-lift with older GHCs but we can't add new boot libs in a minor version of GHC). LMK if you'd prefer that to the current version.

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Bodigrim commented Dec 28, 2025

If we want new releases of text to be backportable to older GHCs then I will need to introduce some CPP to allow building with GHC when th-lift isn't a boot lib (note that end users can build th-lift with older GHCs but we can't add new boot libs in a minor version of GHC). LMK if you'd prefer that to the current version.

Yes please. We can always rip off CPP once last GHC releases in 9.10 and 9.12 series are out.

@TeofilC TeofilC force-pushed the wip/th-lift branch 5 times, most recently from 3740ed5 to fabfb34 Compare January 10, 2026 22:07
@TeofilC TeofilC marked this pull request as ready for review January 10, 2026 22:15
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Bodigrim reviewed Jan 17, 2026
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@TeofilC
Use template-haskell-lift for GHC>=9.14
5340a71 
This new boot library should be more stable than template-haskell and
should eventually allow us to remove much of the CPP around TH.

It will also make it easier for end-users to reinstall template-haskell
as it will no longer be used by any boot libraries
@Lysxia Lysxia merged commit d2a183e into haskell:master Jan 20, 2026
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Lysxia commented Jan 20, 2026

Thanks a lot!

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Bodigrim commented Jan 22, 2026

@TeofilC could you please confirm that text submodule in GHC can be bumped to the current master (a1fd01d)?

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TeofilC commented Jan 25, 2026

@TeofilC could you please confirm that text submodule in GHC can be bumped to the current master (a1fd01d)?

I checked and GHC compiles with the latest master of text

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