Modulehorizon-config-shell-0.12.1GHC2024

Horizon.Config.Solve

Turn a set of roots into a complete, resolved package closure by driving cabal's own solver, then reading its plan.json. This is what the solve verb means: instead of the config listing every package by hand, it names the roots (root "cabal-install") and the indices, and the solver expands the full transitive closure — so a dependency like network can never be silently dropped.

The solve is real IO (it runs cabal against the pinned compiler and the declared indices), so it lives here in the shell, not in the pure config fold. It reuses cabal's SAT solver rather than reimplementing resolution; the plan it emits records each package's version and which index it came from, which is exactly the provenance the generated package set needs.

4 types
2 values

Packagehorizon-config-shell-0.12.1
Exports6
LanguageGHC2024
LicenceBSD-3-Clause
SourceSolve.hs

datadata SolveInput

Everything a solve needs. The compiler, base set and tools are the pinned toolchain's (Horizon.Config.Toolchain); the indices are the declared index names, mapped to their repository configuration.

Constructors

SolveInput
- siGhc :: FilePath
  path to the pinned ghc binary
- siIndices :: [Text]
  declared indices, in precedence order
- siIndexState :: Maybe IndexState
  the state Hackage is read at (the newest, when absent)
- siAllowNewer :: [Text]
  packages whose upper bounds are relaxed (empty = allow-newer: all)
- siRoots :: [Text]
  the roots to expand
- siBase :: [Text]
  package names the base set already provides (never regenerate these)
- siFlags :: [(Text, [Text])]
  per-package flag settings (+f / -f) the build will use
- siPins :: [(Text, Text)]
  Hackage versions the config pins by hand
- siTools :: [FilePath]
  the toolchain's cabal-install, pkg-config and native libraries, every output
- siSources :: [GitPin]
  the declared git packages, which the solve builds from source
- siRepositories :: [SecureRepository]
  the secure repositories the config declares, which an index may name
- siHeld :: [(Text, Text)]
  the versions a lower set holds, which a set layered on it solves around

Instances2Eq, Show

Eq SolveInputDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve
Show SolveInputDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve

datadata Resolved

One resolved package: its name, version and the index it was drawn from (the repo.uri from the plan, mapped back to an index name).

Constructors

Resolved
- resName :: Text
- resVersion :: Text
- resIndex :: Text

Instances2Eq, Show

Eq ResolvedDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve
Show ResolvedDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve

datadata GitPin

A declared git package as the solve sees it: its repository, revision and subdirectory. It is not in any index, so the probe project names it as a source-repository-package; a root may then be a git package, and the plan resolves its dependencies like any other.

Constructors

GitPin
- gitUrl :: Text
- gitRevision :: Text
- gitSubdir :: Maybe Text

Instances2Eq, Show

Eq GitPinDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve
Show GitPinDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve

valuesourceStanza :: GitPin -> [Text]

A git package as a source-repository-package of the probe project.

datadata SolveResult

The outcome of a solve: the packages to generate, and the boot libraries the compiler ships that the base set does not expose (which the generated set must mark null).

Constructors

SolveResult
- srPackages :: [Resolved]
  configured, repo-sourced, minus base
- srGhcProvided :: [Text]
  boot ∖ base ∖ generated — the nulls

Instances2Eq, Show

Eq SolveResultDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve
Show SolveResultDefined in horizon-config-shell-0.12.1 · Horizon.Config.Solve

valuesolve :: SolveInput -> IO SolveResult

Resolve the roots to their full transitive closure. Returns the configured repo packages to generate (the boot / GHC-bundled pre-existing packages are inherited, not generated), each with its version and source index, plus the boot libraries the compiler ships that the base set does not expose.