py: Combine load_attr and store_attr type methods into one (attr).

This simplifies the API for objects and reduces code size (by around 400
bytes on Thumb2, and around 2k on x86).  Performance impact was measured
with Pystone score, but change was barely noticeable.

1 files changed, 14 insertions, 15 deletions

diff --git a/py/objnamedtuple.c b/py/objnamedtuple.c
index 1996b4121..9cc6da1b7 100644
--- a/py/objnamedtuple.c
+++ b/py/objnamedtuple.c
@@ -68,20 +68,20 @@ STATIC void namedtuple_print(void (*print)(void *env, const char *fmt, ...), voi
     print(env, ")");
 }
 
-STATIC void namedtuple_load_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
-    mp_obj_namedtuple_t *self = self_in;
-    int id = namedtuple_find_field((mp_obj_namedtuple_type_t*)self->tuple.base.type, attr);
-    if (id == -1) {
-        return;
+STATIC void namedtuple_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
+    if (dest[0] == MP_OBJ_NULL) {
+        // load attribute
+        mp_obj_namedtuple_t *self = self_in;
+        int id = namedtuple_find_field((mp_obj_namedtuple_type_t*)self->tuple.base.type, attr);
+        if (id == -1) {
+            return;
+        }
+        dest[0] = self->tuple.items[id];
+    } else {
+        // delete/store attribute
+        // provide more detailed error message than we'd get by just returning
+        nlr_raise(mp_obj_new_exception_msg(&mp_type_AttributeError, "can't set attribute"));
     }
-    dest[0] = self->tuple.items[id];
-}
-
-STATIC bool namedtuple_store_attr(mp_obj_t self_in, qstr attr, mp_obj_t value) {
-    (void)self_in;
-    (void)attr;
-    (void)value;
-    nlr_raise(mp_obj_new_exception_msg(&mp_type_AttributeError, "can't set attribute"));
 }
 
 STATIC mp_obj_t namedtuple_make_new(mp_obj_t type_in, mp_uint_t n_args, mp_uint_t n_kw, const mp_obj_t *args) {
@@ -154,8 +154,7 @@ STATIC mp_obj_t mp_obj_new_namedtuple_type(qstr name, mp_uint_t n_fields, mp_obj
     o->base.make_new = namedtuple_make_new;
     o->base.unary_op = mp_obj_tuple_unary_op;
     o->base.binary_op = mp_obj_tuple_binary_op;
-    o->base.load_attr = namedtuple_load_attr;
-    o->base.store_attr = namedtuple_store_attr;
+    o->base.attr = namedtuple_attr;
     o->base.subscr = mp_obj_tuple_subscr;
     o->base.getiter = mp_obj_tuple_getiter;
     o->base.bases_tuple = (mp_obj_t)&namedtuple_base_tuple;