diff --git a/corpus/edigits_like.langexp b/corpus/edigits_like.langexp
index a41c95c..874dc4c 100644
--- a/corpus/edigits_like.langexp
+++ b/corpus/edigits_like.langexp
@@ -257,17 +257,16 @@ test_k 'n 'k : Int Int -> Bool = {
     (simple_name_identifier)
     (argument_name_identifier)
     (argument_name_identifier)
-    (function_type
+    (simple_type
+      (simple_type_identifier))
+    (simple_type
+      (simple_type_identifier))
+    (reference_type
       (simple_type
-        (simple_type_identifier))
+        (simple_type_identifier)))
+    (reference_type
       (simple_type
-        (simple_type_identifier))
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+        (simple_type_identifier)))
     (block
       (empty_lines)
       (condition
@@ -358,12 +357,11 @@ test_k 'n 'k : Int Int -> Bool = {
   (function_definition
     (simple_name_identifier)
     (argument_name_identifier)
-    (function_type
+    (simple_type
+      (simple_type_identifier))
+    (reference_type
       (simple_type
-        (simple_type_identifier))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+        (simple_type_identifier)))
     (block
       (empty_lines)
       (match
@@ -455,14 +453,13 @@ test_k 'n 'k : Int Int -> Bool = {
     (simple_name_identifier)
     (argument_name_identifier)
     (argument_name_identifier)
-    (function_type
+    (simple_type
+      (simple_type_identifier))
+    (simple_type
+      (simple_type_identifier))
+    (reference_type
       (simple_type
-        (simple_type_identifier))
-      (simple_type
-        (simple_type_identifier))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+        (simple_type_identifier)))
     (block
       (empty_lines)
       (condition
diff --git a/corpus/test.langexp b/corpus/test.langexp
index edfb5ff..02d62b6 100644
--- a/corpus/test.langexp
+++ b/corpus/test.langexp
@@ -445,13 +445,12 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
         (index_literal)))
     (simple_name_identifier)
     (argument_name_identifier)
-    (function_type
-      (annotation_identifier)
+    (annotation_identifier)
+    (simple_type
+      (simple_type_identifier))
+    (reference_type
       (simple_type
-        (simple_type_identifier))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+        (simple_type_identifier)))
     (match
       (name_expression
         (argument_name_identifier))
@@ -1102,13 +1101,12 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
     (simple_name_identifier)
     (argument_name_identifier)
     (argument_name_identifier)
-    (function_type
-      (reference_type
-        (simple_type
-          (argument_type_identifier)))
-      (reference_type
-        (simple_type
-          (argument_type_identifier))))
+    (reference_type
+      (simple_type
+        (argument_type_identifier)))
+    (reference_type
+      (simple_type
+        (argument_type_identifier)))
     (comma_expression
       (comma_expression
         (match
@@ -1161,16 +1159,15 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
     (definition_info
       (info))
     (simple_name_identifier)
-    (function_type
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
     (operator_expression
       (operator_expression
         (name_expression
@@ -1203,16 +1200,15 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
     (simple_name_identifier)
     (argument_name_identifier)
     (argument_name_identifier)
-    (function_type
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
     (constructor
       (simple_type
         (simple_type_identifier))
@@ -1227,16 +1223,15 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
     (simple_name_identifier)
     (argument_name_identifier)
     (argument_name_identifier)
-    (function_type
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))
-      (reference_type
-        (simple_type
-          (simple_type_identifier))))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
+    (reference_type
+      (simple_type
+        (simple_type_identifier)))
     (constructor
       (simple_type
         (simple_type_identifier))
@@ -1251,12 +1246,11 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
   (empty_lines)
   (function_definition
     (simple_name_identifier)
-    (function_type
+    (simple_type
+      (simple_type_identifier))
+    (reference_type
       (simple_type
-        (simple_type_identifier))
-      (reference_type
-        (simple_type
-          (simple_type_identifier)))))
+        (simple_type_identifier))))
   (empty_lines)
   (function_definition
     (definition_info
@@ -1496,21 +1490,20 @@ functional_arguments_test 'x 'y : (( Int -> Int )) (( Float <- Float -> Float ))
     (argument_name_identifier)
     (argument_name_identifier)
     (function_type
-      (function_type
+      (simple_type
+        (simple_type_identifier))
+      (reference_type
         (simple_type
-          (simple_type_identifier))
-        (reference_type
-          (simple_type
-            (simple_type_identifier))))
-      (function_type
+          (simple_type_identifier))))
+    (function_type
+      (simple_type
+        (simple_type_identifier))
+      (reference_type
         (simple_type
-          (simple_type_identifier))
-        (reference_type
-          (simple_type
-            (simple_type_identifier)))
-        (reference_type
-          (simple_type
-            (simple_type_identifier)))))
+          (simple_type_identifier)))
+      (reference_type
+        (simple_type
+          (simple_type_identifier))))
     (name_expression
       (simple_name_identifier)))
   (empty_lines))
diff --git a/grammar.js b/grammar.js
index cbaa085..ecaa181 100644
--- a/grammar.js
+++ b/grammar.js
@@ -53,7 +53,7 @@ module.exports = grammar({
       )),
       optional(seq(
         ':',
-        choice($.function_type, $._annotated_type),
+        repeat1($._annotated_type),
       )),
       choice(seq('=', choice(prec(2, choice($.block, $.array)), seq($._super_expression, ';'))), ';'),
     ),
@@ -223,8 +223,10 @@ module.exports = grammar({
     ),
 
     function_type: $ => seq(
+      '((',
       $._annotated_type,
       repeat1($._annotated_type),
+      '))',
     ),
 
     // add annotations to in all types ??
@@ -263,7 +265,7 @@ module.exports = grammar({
         $.tuple_type,
         //$.function_type,
       ), ')'),
-      seq('((', $.function_type, '))'),
+      $.function_type,
     ),
 
     // --- comments