Configuration transition

[telser]

Could we get a release that supports both the dhall or toml configurations to help transition?

Given that stackage only very recently moved to GHC-9.4.5, it seems likely that many users will not be able to upgrade to 2.6 soon. Would a branch from 2.5.0, be possible?

[ocharles]

Hi @telser. I'm reluctant to have weeder support two configuration formats - and we moved to toml-reader with the explicit goal to reduce the dependency graph. The good news is that migrating from Dhall can be done programmatically!

let concatSep = https://prelude.dhall-lang.org/v19.0.0/Text/concatSep.dhall

let map = https://prelude.dhall-lang.org/v19.0.0/List/map.dhall

let to-toml = \(config : {type-class-roots : Bool, roots : List Text}) ->
       "type-class-roots = " ++ (if config.type-class-roots then "true" else "false") ++ "\n" ++
       "roots = [" ++ concatSep ",\n" (map Text Text (\(t : Text) -> "'" ++ t ++ "'") config.roots)  ++ "]"

in to-toml

If you stick that in to-toml.dhall, you should then be able to run:

dhall-to-text <<< './to-toml.dhall weeder.dhall' > weeder.toml

Does that help?