[Openmcl-devel] hash-table-hash-function

[Chris Dean]

[Looks like my earlier message was scrubbed, so I'll repost.]

Is there an existing way to extract the hash-function from a hash-table?
Turns out that I need one to properly serialize some data structures.

In case there isn't one, I have a patch below to add a
hash-table-hash-function and put it in the CCL package.

Cheers,
Chris Dean


Index: lib/ccl-export-syms.lisp
===================================================================
--- lib/ccl-export-syms.lisp	(revision 11952)
+++ lib/ccl-export-syms.lisp	(working copy)
@@ -271,6 +271,8 @@
      init-list-default
      fset
 
+     hash-table-hash-function
+
 					; Files.
      mac-default-directory
      current-directory
Index: level-0/l0-hash.lisp
===================================================================
--- level-0/l0-hash.lisp	(revision 11952)
+++ level-0/l0-hash.lisp	(working copy)
@@ -576,6 +576,13 @@
       (if (eql 0 f) #'eq #'eql)
       f)))
 
+(defun hash-table-hash-function (hash)
+  "Return the hashing function HASH-TABLE was created with."
+  (let ((fn (nhash.keytransF (require-type hash 'hash-table))))
+    (if (fixnump fn)
+        nil
+        fn)))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
 ;; nearly-lock-free hash tables