Export a few more BuildTarget utils

Cabal/Distribution/Simple/BuildTarget.hs

@@ -14,10 +14,14 @@ module Distribution.Simple.BuildTarget (
     -- * Build targets
     BuildTarget(..),
     readBuildTargets,
+    showBuildTarget,
+    QualLevel(..),
+    buildTargetComponentName,
 
     -- * Parsing user build targets
     UserBuildTarget,
     readUserBuildTargets,
+    showUserBuildTarget,
     UserBuildTargetProblem(..),
     reportUserBuildTargetProblems,
 
@@ -130,6 +134,11 @@ data BuildTarget =
 
 instance Binary BuildTarget
 
+buildTargetComponentName :: BuildTarget -> ComponentName
+buildTargetComponentName (BuildTargetComponent cn)   = cn
+buildTargetComponentName (BuildTargetModule    cn _) = cn
+buildTargetComponentName (BuildTargetFile      cn _) = cn
+
 -- | Read a list of user-supplied build target strings and resolve them to
 -- 'BuildTarget's according to a 'PackageDescription'. If there are problems
 -- with any of the targets e.g. they don't exist or are misformatted, throw an
@@ -232,6 +241,10 @@ showUserBuildTarget = intercalate ":" . components
     components (UserBuildTargetDouble s1 s2)    = [s1,s2]
     components (UserBuildTargetTriple s1 s2 s3) = [s1,s2,s3]
 
+showBuildTarget :: QualLevel -> PackageId -> BuildTarget -> String
+showBuildTarget ql pkgid bt =
+    showUserBuildTarget (renderBuildTarget ql bt pkgid)
+
 
 -- ------------------------------------------------------------
 -- * Resolving user targets to build targets