chore: support json output

2 files changed, 13 insertions, 0 deletions

diff --git a/sh.cabal b/sh.cabal
index d5fce58..da19b23 100644
--- a/sh.cabal
+++ b/sh.cabal
@@ -14,6 +14,7 @@ library
     default-language: GHC2021
     ghc-options:      -Wall
     build-depends:
+        aeson,
         base,
         bytestring,
         haskell-src-meta,
diff --git a/src/Process/Shell.hs b/src/Process/Shell.hs
index 87d22df..24bea95 100644
--- a/src/Process/Shell.hs
+++ b/src/Process/Shell.hs
@@ -9,11 +9,15 @@
 module Process.Shell
   ( sh,
     Quotable (..),
+    ExitCodeException (..),
+    DecodeException (..),
   )
 where
 
+import Control.Exception (Exception, throw)
 import Control.Monad
 import Control.Monad.Reader
+import Data.Aeson
 import Data.ByteString qualified as B
 import Data.ByteString.Lazy qualified as LB
 import Data.ByteString.Lazy.UTF8 qualified as LB
@@ -67,6 +71,14 @@ instance Outputable T.Text where
 instance Outputable LT.Text where
   fromLBS = LT.decodeUtf8
 
+data DecodeException = DecodeException
+  deriving (Show)
+
+instance Exception DecodeException
+
+instance (FromJSON a) => Outputable a where
+  fromLBS = fromMaybe (throw DecodeException) . decode
+
 class Quotable a where
   toString :: a -> String
   default toString :: (Show a) => a -> String