aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--lib/Distribution/Helper.hs15
-rw-r--r--src/CabalHelper/Compiletime/Types.hs14
2 files changed, 22 insertions, 7 deletions
diff --git a/lib/Distribution/Helper.hs b/lib/Distribution/Helper.hs
index 73c3438..2f9493e 100644
--- a/lib/Distribution/Helper.hs
+++ b/lib/Distribution/Helper.hs
@@ -30,6 +30,9 @@ Portability : POSIX
-}
module Distribution.Helper (
+ -- * Type Variable Naming Conventions
+ -- $type-conventions
+
-- * Running Queries
Query
, runQuery
@@ -143,6 +146,18 @@ import Distribution.Verbosity (silent, deafening)
--import Distribution.Package (packageName, packageVersion)
import Distribution.Simple.GHC as GHC (configure)
+-- $type-conventions
+-- Throughout the API we use the following conventions for type variables:
+--
+-- * @pt@ stands for "project type", when instantiated is always of kind
+-- 'ProjType'.
+--
+-- * @c@ stands for "cache". It is used internally to make the cache
+-- inaccessible for some parts of the implementation. Users of the API may
+-- ignore it. See the internal 'qeCacheRef' field accessor of 'QueryEnv' for
+-- details.
+
+
-- | A lazy, cached, query against a package's Cabal configuration. Use
-- 'runQuery' to execute it.
newtype Query pt a = Query
diff --git a/src/CabalHelper/Compiletime/Types.hs b/src/CabalHelper/Compiletime/Types.hs
index 3c6ff73..5a19261 100644
--- a/src/CabalHelper/Compiletime/Types.hs
+++ b/src/CabalHelper/Compiletime/Types.hs
@@ -93,15 +93,15 @@ data DistDir (pt :: ProjType) where
-- | Environment for running a 'Query' value. The real constructor is
-- not exposed, use the 'mkQueryEnv' smart constructor instead. The field
-- accessors are exported and may be used to override the defaults, see below.
-type QueryEnv (proj_type :: ProjType)
- = QueryEnvI (QueryCache proj_type) proj_type
+type QueryEnv (pt :: ProjType)
+ = QueryEnvI QueryCache pt
-data QueryEnvI cache (proj_type :: ProjType) = QueryEnv
+data QueryEnvI c (pt :: ProjType) = QueryEnv
{ qeReadProcess
:: !(Maybe FilePath -> FilePath -> [String] -> String -> IO String)
-- ^ Field accessor for 'QueryEnv'. Function used to to start
-- processes. Useful if you need to, for example, redirect standard error
- -- output away from the user\'s terminal.
+ -- output of programs started by cabal-helper.
, qePrograms :: !Programs
-- ^ Field accessor for 'QueryEnv'.
@@ -109,17 +109,17 @@ data QueryEnvI cache (proj_type :: ProjType) = QueryEnv
, qeCompPrograms :: !CompPrograms
-- ^ Field accessor for 'QueryEnv'.
- , qeProjLoc :: !(ProjLoc proj_type)
+ , qeProjLoc :: !(ProjLoc pt)
-- ^ Field accessor for 'QueryEnv'. Defines path to the project directory,
-- i.e. a directory containing a @cabal.project@ file
- , qeDistDir :: !(DistDir proj_type)
+ , qeDistDir :: !(DistDir pt)
-- ^ Field accessor for 'QueryEnv'. Defines path to the @dist/@ or
-- @dist-newstyle/@ directory, aka. /builddir/ in Cabal terminology.
- , qeCacheRef :: !(IORef cache)
-- ^ Cache for query results, only accessible when type parameter @cache@ is
-- instantiated and not forall quantified.
+ , qeCacheRef :: !(IORef (c pt))
}
data QueryCache pt = QueryCache