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base repository: NixOS/nixpkgs
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  • 2 commits
  • 2 files changed
  • 1 contributor

Commits on Jul 3, 2020

  1. haskellPackages: doHaddockInterfaces 

    This adds a new builder option `doHaddockInterfaces` to enable the -haddock flag in GHC,
which results in Haddock comments parsed at compile-time and embedded in
interface files. These are used by the :doc command in GHCi, as well as IDE
tools like ghcide and hls to display docs on hover.

The `-haddock` flag has been around since at least 8.2, even though it does not
get a mention in the GHC Users guide.

There are two downsides to turning on this flag:

1. Increased compile times, since Haddocks must be parsed and then encoded
2. Haddock parse errors now become compile errors
   (https://gitlab.haskell.org/ghc/ghc/-/issues/8944)

Item 2 in particular can be quite problematic for benchmarks and test suites,
where Haddock parse errors would not be a consideration.
This explains the default setting for `doHaddockInterfaces` being `doHaddock && !doCheck `.
Once the problem is [fixed](https://gitlab.haskell.org/ghc/ghc/-/issues/8944) in
GHC, the `doHaddockInterfaces` default value can be updated to be always on in
certain GHC versions.
    @pepeiborra @peti
    pepeiborra authored and peti committed Jul 3, 2020
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  2. Enable doHaddockInterfaces by default 

    This is a priori an experiment to find out how many packages break
    @pepeiborra @peti
    pepeiborra authored and peti committed Jul 3, 2020
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