- Improved handling of type variables.

1 files changed, 21 insertions, 10 deletions

diff --git a/stdlib/source/lux/meta/type/check.lux b/stdlib/source/lux/meta/type/check.lux
index bd49a5588..d6589760e 100644
--- a/stdlib/source/lux/meta/type/check.lux
+++ b/stdlib/source/lux/meta/type/check.lux
@@ -144,16 +144,6 @@
   (function [context]
     (ex;throw exception message)))
 
-(def: (apply-type! funcT argT)
-  (-> Type Type (Check Type))
-  (function [context]
-    (case (type;apply (list argT) funcT)
-      #;None
-      (ex;throw Invalid-Type-Application (type;to-text (#;Apply argT funcT)))
-
-      (#;Some output)
-      (#e;Success [context output]))))
-
 (def: #export existential
   {#;doc "A producer of existential types."}
   (Check [Nat Type])
@@ -296,6 +286,27 @@
     (#e;Success [(set@ #;var-bindings value context)
                  []])))
 
+(def: (apply-type! funcT argT)
+  (-> Type Type (Check Type))
+  (case funcT
+    (#;Var func-id)
+    (do Monad<Check>
+      [? (concrete? func-id)]
+      (if ?
+        (do @
+          [funcT' (read func-id)]
+          (apply-type! funcT' argT))
+        (throw Invalid-Type-Application (type;to-text (#;Apply argT funcT)))))
+
+    _
+    (function [context]
+      (case (type;apply (list argT) funcT)
+        #;None
+        (ex;throw Invalid-Type-Application (type;to-text (#;Apply argT funcT)))
+
+        (#;Some output)
+        (#e;Success [context output])))))
+
 (type: #export Ring (Set Var))
 
 (def: empty-ring Ring (set;new number;Hash<Nat>))