xo-interpreter2 stack: refactor: move cons() pm to object2/

include/xo/procedure2/ObjectPrimitives.hpp

@@ -21,9 +21,12 @@ namespace xo {
             using AAllocator = xo::mm::AAllocator;
 
         public:
-            /** create primitive for fetching nth element of a sequence **/
+            /** create primitive: fetch nth element of a sequence **/
             static DPrimitive_gco_2_gco_gco * make_nth_pm(obj<AAllocator> mm);
 
+            /** create primitive: create cons cell **/
+            static DPrimitive_gco_2_gco_gco * make_cons_pm(obj<AAllocator> mm);
+
             /** create pirmitive for creating a dictionary instance **/
             static DPrimitive_gco_0 * make_dict_make_pm(obj<AAllocator> mm);
 

src/procedure2/ObjectPrimitives.cpp

@@ -6,6 +6,7 @@
 #include "ObjectPrimitives.hpp"
 #include <xo/object2/Dictionary.hpp>
 #include <xo/object2/Sequence.hpp>
+#include <xo/object2/List.hpp>
 #include <xo/object2/Integer.hpp>
 #include <xo/printable2/Printable.hpp>
 #include <xo/stringtable2/String.hpp>
@@ -44,6 +45,28 @@ namespace xo {
             return DPrimitive_gco_2_gco_gco::_make(mm, "nth", &xfer_nth);
         }
 
+        // ----- cons -----
+
+        obj<AGCObject>
+        xfer_cons(obj<ARuntimeContext> rcx,
+                  obj<AGCObject> car,
+                  obj<AGCObject> cdr)
+        {
+            (void)rcx;
+
+            auto cdr_list = obj<AGCObject,DList>::from(cdr);
+
+            return DList::cons(rcx.allocator(),
+                               car,
+                               cdr_list.data());
+        }
+
+        DPrimitive_gco_2_gco_gco *
+        ObjectPrimitives::make_cons_pm(obj<AAllocator> mm)
+        {
+            return DPrimitive_gco_2_gco_gco::_make(mm, "cons", &xfer_cons);
+        }
+
         // ----- dict_make -----
 
         obj<AGCObject>

src/procedure2/procedure2_register_primitives.cpp

@@ -62,6 +62,7 @@ namespace xo {
             bool ok = true;
 
             ok = ok & install_aux(sink, ObjectPrimitives::make_nth_pm(mm), flags);
+            ok = ok & install_aux(sink, ObjectPrimitives::make_cons_pm(mm), flags);
             ok = ok & install_aux(sink, ObjectPrimitives::make_dict_make_pm(mm), flags);
             ok = ok & install_aux(sink, ObjectPrimitives::make_dict_upsert_pm(mm), flags);