Add `HshIdx.swap()`

1 files changed, 7 insertions, 1 deletions

diff --git a/include/qntan/Qntan.h b/include/qntan/Qntan.h
index d5e77a7..1dcb005 100644
--- a/include/qntan/Qntan.h
+++ b/include/qntan/Qntan.h
@@ -831,7 +831,7 @@ struct Qntan_HshIdx {
 	size_t (*getCnt)( struct Qntan_HshIdx** );
 	/* Returns number of objects currently present in this collection.
 	 */
-	int  (*addIfNew)( struct Qntan_HshIdx**, void*elm );
+	int  (*addIfNew)( struct Qntan_HshIdx**, void*elm, int idx );
 	/* Returns 0 if 'elm' got copied into the hashtable.
 	 * Returns '-EEXIST' (yep, negated) if 'elm' already exists. Nothing got
 	 * copied anywhere.
@@ -842,6 +842,12 @@ struct Qntan_HshIdx {
 	 * Returns 1 if found object got copied to 'ptrToDst'. The element itelf
 	 * will swill be present in the table.
 	 */
+	int  (*swap)( struct Qntan_HshIdx**, void*elm, void*ptrToDst, int idx );
+	/* Returns 0 if 'elm' got copied into the hashtable.
+	 * Returns 1 is similar to 'Return 0'. BUT: a matching element did already
+	 * exist and this old element now got swapped into 'ptrToDst'.
+	 * Returns negative values to indicate errors.
+	 */
 };