Allow super to take an instance as an argument.

* struct.c (super): Detect structure instance
and resolve it to its type. Recursion eliminated in favor of
imperative approach that eliminates redundant checks.

* txr.1: Description of super updated.

1 files changed, 3 insertions, 2 deletions

diff --git a/txr.1 b/txr.1
index e2f631a4..c57548a7 100644
--- a/txr.1
+++ b/txr.1
@@ -18388,8 +18388,9 @@ has no supertype.
 
 The
 .meta type
-must be either a struct type object, or else
-a symbol which names a struct type.
+argument must be either a struct type object, a
+a symbol which names a struct type (which is resolved to that type),
+or else a structure instance (which is resolved to its structure type).
 
 .coNP Function @ make-struct
 .synb