Use as-pattern

1 files changed, 1 insertions, 4 deletions

diff --git a/src/Env.hs b/src/Env.hs
index 1b98e9f..380addc 100644
--- a/src/Env.hs
+++ b/src/Env.hs
@@ -44,12 +44,9 @@ existsSyml env sym = isJust $ getSyml env sym
 -- environment. It will create a new enviroment if the symbol already exists
 -- (shadowing).
 addSym :: Env -> Sym -> Env
-addSym (Env m parent) (id, typ, pos) = case getSym env id of
+addSym env@(Env m parent) sym@(id, typ, pos) = case getSym env id of
   Nothing -> Env (Map.insert id sym m) parent
   Just s -> Env (Map.singleton id sym) $ Just env
-  where
-    env = (Env m parent)
-    sym = (id, typ, pos)
 
 -- | @addEnv e@ adds a new local environment using @e@ as parent.
 addEnv :: Env -> Env