feat: show exact statement which must be returning at the end of a function

src/main/wacc/parser.scala

@@ -75,15 +75,15 @@ object parser {
 
   // Statements
   private lazy val `<program>` = Program(
-    "begin" ~> many(atomic(`<func>`)),
+    "begin" ~> many(`<func>`),
     `<stmt>` <~ "end"
   )
   private lazy val `<func>` = FuncDecl(
-    `<type>`,
-    `<ident>` <~ "(",
+    atomic(`<type>`),
+    atomic(`<ident>`) <~ "(",
     sepBy(`<param>`, ",") <~ ")" <~ "is",
-    `<stmt>` <~ "end"
-  )
+    `<stmt>`
+  ) <~ "end"
   private lazy val `<param>` = Param(`<type>`, `<ident>`)
   private lazy val `<stmt>`: Parsley[NonEmptyList[Stmt]] =
     sepBy1(`<basic-stmt>`, ";")