Generalized version of dictionaries, with compatibility hacks.
diff --git a/Include/mappingobject.h b/Include/mappingobject.h
new file mode 100644
index 0000000..83c3380
--- /dev/null
+++ b/Include/mappingobject.h
@@ -0,0 +1,43 @@
+/***********************************************************
+Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
+Amsterdam, The Netherlands.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the names of Stichting Mathematisch
+Centrum or CWI not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior permission.
+
+STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
+THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
+FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+******************************************************************/
+
+/*
+Mapping object type -- mapping from object to object.
+These functions set errno for errors. Functions mappingremove() and
+mappinginsert() return nonzero for errors, getmappingsize() returns -1,
+the others NULL. A successful call to mappinginsert() calls INCREF()
+for the inserted item.
+*/
+
+extern typeobject Mappingtype;
+
+#define is_mappingobject(op) ((op)->ob_type == &Mappingtype)
+
+extern object *newmappingobject PROTO((void));
+extern object *mappinglookup PROTO((object *dp, object *key));
+extern int mappinginsert PROTO((object *dp, object *key, object *item));
+extern int mappingremove PROTO((object *dp, object *key));
+extern int getmappingsize PROTO((object *dp));
+extern object *getmappingkey PROTO((object *dp, int i));
+extern object *getmappingkeys PROTO((object *dp));