Sync Unix_Timestamp64 definition with the spec

It now has the 'x' type.

diff --git a/extensions/generic-types.xml b/extensions/generic-types.xml
index fe27d36c9ca460fc4fc16cc514fc54d5731dcd3c..fdab14be815aaf40cd07285606c36654f210071f 100644 (file)
--- a/extensions/generic-types.xml
+++ b/extensions/generic-types.xml
@@ -7,10 +7,10 @@
       (1970-01-01T00:00:00Z)</tp:docstring>
   </tp:simple-type>
 
-  <tp:simple-type name="Unix_Timestamp64" type="t">
-    <tp:docstring>An unsigned 64-bit integer representing time as the number
+  <tp:simple-type name="Unix_Timestamp64" type="x">
+    <tp:docstring>An signed 64-bit integer representing time as the number
       of seconds elapsed since the Unix epoch
-      (1970-01-01T00:00:00Z)</tp:docstring>
+      (1970-01-01T00:00:00Z); negative for times before the epoch</tp:docstring>
 
     <tp:rationale>The Text interface is the only user of Unix_Timestamp so
       far, and we'd like to be Y2038 compatible in future