Define API for accessing tp_iterkeys

include/deemon/object.h

@@ -4845,6 +4845,12 @@ DFUNDEF WUNUSED NONNULL((1, 2)) Dee_ssize_t /* TODO: Refactor more code to use t
 DFUNDEF WUNUSED NONNULL((1, 2)) Dee_ssize_t
 (DCALL DeeObject_Enumerate)(DeeObject *__restrict self, Dee_enumerate_t proc, void *arg);
 
+/* Construct an iterator for the keys of "self". That is:
+ * - everything for which `DeeObject_HasItem()' returns true
+ * - everything passed as "key"-argumented to the callback taken by `DeeObject_Enumerate()' */
+DFUNDEF WUNUSED NONNULL((1)) DREF DeeObject *
+(DCALL DeeObject_IterKeys)(DeeObject *__restrict self);
+
 /* Same as `DeeObject_Enumerate()', but only valid when "self" uses integers for indices
  * or is a mapping where all keys are integers. In the former case, [start,end) can be
  * given in order to only enumerate indices that fall within that range (any index that

include/deemon/super.h

@@ -152,6 +152,7 @@ DFUNDEF WUNUSED NONNULL((1, 2, 3)) Dee_ssize_t (DCALL DeeObject_TForeach)(DeeTyp
 DFUNDEF WUNUSED NONNULL((1, 2, 3)) Dee_ssize_t (DCALL DeeObject_TForeachPair)(DeeTypeObject *tp_self, DeeObject *self, Dee_foreach_pair_t proc, void *arg);
 DFUNDEF WUNUSED NONNULL((1, 2, 3)) Dee_ssize_t (DCALL DeeObject_TEnumerate)(DeeTypeObject *tp_self, DeeObject *self, Dee_enumerate_t proc, void *arg);
 DFUNDEF WUNUSED NONNULL((1, 2, 3)) Dee_ssize_t (DCALL DeeObject_TEnumerateIndex)(DeeTypeObject *tp_self, DeeObject *self, Dee_enumerate_index_t proc, void *arg, size_t start, size_t end);
+DFUNDEF WUNUSED NONNULL((1, 2)) DREF DeeObject *(DCALL DeeObject_TIterKeys)(DeeTypeObject *tp_self, DeeObject *self);
 DFUNDEF WUNUSED NONNULL((1, 2)) DREF DeeObject *(DCALL DeeObject_TIter)(DeeTypeObject *tp_self, DeeObject *self);
 DFUNDEF WUNUSED NONNULL((1, 2)) DREF DeeObject *(DCALL DeeObject_TIterNext)(DeeTypeObject *tp_self, DeeObject *self);
 DFUNDEF WUNUSED NONNULL((1, 2)) DREF DeeObject *(DCALL DeeObject_TSizeOb)(DeeTypeObject *tp_self, DeeObject *self);

src/deemon/objects/super.c

@@ -626,6 +626,11 @@ super_enumerate_index(Super *__restrict me, Dee_enumerate_index_t proc,
 	return DeeObject_TEnumerateIndex(me->s_type, me->s_self, proc, arg, start, end);
 }
 
+PRIVATE WUNUSED NONNULL((1)) DREF DeeObject *DCALL
+super_iterkeys(Super *__restrict self) {
+	return DeeObject_TIterKeys(self->s_type, self->s_self);
+}
+
 PRIVATE WUNUSED NONNULL((1, 2)) int DCALL
 super_bounditem(Super *self, DeeObject *index) {
 	return DeeObject_TBoundItem(self->s_type, self->s_self, index);
@@ -787,7 +792,7 @@ PRIVATE struct type_seq super_seq = {
 	/* .tp_foreach_pair               = */ (Dee_ssize_t (DCALL *)(DeeObject *__restrict, Dee_foreach_pair_t, void *))&super_foreach_pair,
 	/* .tp_enumerate                  = */ (Dee_ssize_t (DCALL *)(DeeObject *__restrict, Dee_enumerate_t, void *))&super_enumerate,
 	/* .tp_enumerate_index            = */ (Dee_ssize_t (DCALL *)(DeeObject *__restrict, Dee_enumerate_index_t, void *, size_t, size_t))&super_enumerate_index,
-	/* .tp_iterkeys                   = */ NULL,
+	/* .tp_iterkeys                   = */ (DREF DeeObject *(DCALL *)(DeeObject *__restrict))&super_iterkeys,
 	/* .tp_bounditem                  = */ (int (DCALL *)(DeeObject *, DeeObject *))&super_bounditem,
 	/* .tp_hasitem                    = */ (int (DCALL *)(DeeObject *, DeeObject *))&super_hasitem,
 	/* .tp_size                       = */ (size_t (DCALL *)(DeeObject *__restrict))&super_size,

src/deemon/runtime/operator.c

@@ -19767,10 +19767,25 @@ DEFINE_OPERATOR(Dee_ssize_t, Enumerate,
 	          unlikely(DeeType_InheritIter(tp_self) && tp_self->tp_seq->tp_enumerate))
 		return (*tp_self->tp_seq->tp_enumerate)(self, proc, arg);
 	return DeeError_Throwf(&DeeError_NotImplemented,
-	                       "Cannot enumerate non-sequence type `%r'",
+	                       "Cannot enumerate keys of non-sequence type `%r'",
 	                       tp_self);
 }
 
+/* Construct an iterator for the keys of "self". That is:
+ * - everything for which `DeeObject_HasItem()' returns true
+ * - everything passed as "key"-argumented to the callback taken by `DeeObject_Enumerate()' */
+DEFINE_OPERATOR(DREF DeeObject *, IterKeys,
+                (DeeObject *RESTRICT_IF_NOTYPE self)) {
+	LOAD_TP_SELF;
+	if likely(likely(tp_self->tp_seq && tp_self->tp_seq->tp_iterkeys) ||
+	          unlikely(DeeType_InheritIter(tp_self) && tp_self->tp_seq->tp_iterkeys))
+		return (*tp_self->tp_seq->tp_iterkeys)(self);
+	DeeError_Throwf(&DeeError_NotImplemented,
+	                "Cannot enumerate keys of non-sequence type `%r'",
+	                tp_self);
+	return NULL;
+}
+
 /* Same as `DeeObject_Enumerate()', but only valid when "self" uses integers for indices
  * or is a mapping where all keys are integers. In the former case, [start,end)
  * can be given in order to allow the implementation to only enumerate indices that fall