Fix bug with bringing functor argument instances into scope; Ref demo, minus prose

1 files changed, 27 insertions, 0 deletions

diff --git a/demo/refFun.ur b/demo/refFun.ur
new file mode 100644
index 00000000..d58acee5
--- /dev/null
+++ b/demo/refFun.ur
@@ -0,0 +1,27 @@
+functor Make(M : sig
+                 type data
+                 val inj : sql_injectable data
+             end) = struct
+
+    type ref = int
+
+    sequence s
+    table t : { Id : int, Data : M.data }
+
+    fun new d =
+        id <- nextval s;
+        () <- dml (INSERT INTO t (Id, Data) VALUES ({id}, {d}));
+        return id
+
+    fun read r =
+        o <- oneOrNoRows (SELECT t.Data FROM t WHERE t.Id = {r});
+        return (case o of
+            None => error <xml>You already deleted that ref!</xml>
+          | Some r => r.T.Data)
+
+    fun write r d =
+        dml (UPDATE t SET Data = {d} WHERE Id = {r})
+
+    fun delete r =
+        dml (DELETE FROM t WHERE Id = {r})
+end