Add 'hadrian/' from commit '45f3bff7016a2a0cd9a5455a882ced984655e90b'

git-subtree-dir: hadrian
git-subtree-mainline: 575b35f4cdc18045bccd42d341d6f25d95c0696c
git-subtree-split: 45f3bff7016a2a0cd9a5455a882ced984655e90b

1 files changed, 29 insertions, 0 deletions

diff --git a/hadrian/src/Hadrian/Target.hs b/hadrian/src/Hadrian/Target.hs
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+module Hadrian.Target (Target, target, context, builder, inputs, outputs) where
+
+import Development.Shake.Classes
+import GHC.Generics
+
+-- | Each invocation of a builder is fully described by a 'Target', which
+-- comprises a build context (type variable @c@), a builder (type variable @b@),
+-- a list of input files and a list of output files. For example:
+--
+-- @
+-- preludeTarget = Target (GHC.Context) (GHC.Builder)
+--     { context = Context Stage1 base profiling
+--     , builder = Ghc Stage1
+--     , inputs = ["libraries/base/Prelude.hs"]
+--     , outputs = ["build/stage1/libraries/base/Prelude.p_o"] }
+-- @
+data Target c b = Target
+    { context :: c          -- ^ Current build context
+    , builder :: b          -- ^ Builder to be invoked
+    , inputs  :: [FilePath] -- ^ Input files for the builder
+    , outputs :: [FilePath] -- ^ Files to be produced
+    } deriving (Eq, Generic, Show)
+
+target :: c -> b -> [FilePath] -> [FilePath] -> Target c b
+target = Target
+
+instance (Binary   c, Binary   b) => Binary   (Target c b)
+instance (Hashable c, Hashable b) => Hashable (Target c b)
+instance (NFData   c, NFData   b) => NFData   (Target c b)