Allow lambda expressions without explicit paren

src/Eval.hs

@@ -54,8 +54,6 @@ evalAST env term
         (errorWithoutStackTrace $ "Variable " ++ name ++ " not defined")
         name env
 
--- https://github.com/barry-jay-personal/typed_tree_calculus/blob/main/typed_program_analysis.pdf
--- Chapter 4: Lambda-Abstraction
 elimLambda :: TricuAST -> TricuAST
 elimLambda = go
   where
@@ -68,9 +66,9 @@ elimLambda = go
       where
         triageBody =
           (SApp (SApp TLeaf (SApp (SApp TLeaf (SVar a)) (SVar b))) (SVar c))
-    -- Compose optimization
+    -- Composition optimization
     go (SLambda [f] (SLambda [g] (SLambda [x] body))) 
-      | body == composeBody = _COMPOSE
+      | body == composeBody        = _COMPOSE
       where
         composeBody = SApp (SVar f) (SApp (SVar g) (SVar x))
     -- General elimination