py/objnamedtuple: Allow to reuse namedtuple basic functionality.

By declaring interface in objnamedtuple.h and introducing a helper
allocation function.

py/objnamedtuple.c

@@ -30,20 +30,11 @@
 #include "py/objtuple.h"
 #include "py/runtime.h"
 #include "py/objstr.h"
+#include "py/objnamedtuple.h"
 
 #if MICROPY_PY_COLLECTIONS
 
-typedef struct _mp_obj_namedtuple_type_t {
+size_t mp_obj_namedtuple_find_field(const mp_obj_namedtuple_type_t *type, qstr name) {
-    mp_obj_type_t base;
-    size_t n_fields;
-    qstr fields[];
-} mp_obj_namedtuple_type_t;
-
-typedef struct _mp_obj_namedtuple_t {
-    mp_obj_tuple_t tuple;
-} mp_obj_namedtuple_t;
-
-STATIC size_t namedtuple_find_field(const mp_obj_namedtuple_type_t *type, qstr name) {
     for (size_t i = 0; i < type->n_fields; i++) {
         if (type->fields[i] == name) {
             return i;
@@ -88,7 +79,7 @@ STATIC void namedtuple_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
             return;
         }
         #endif
-        size_t id = namedtuple_find_field((mp_obj_namedtuple_type_t*)self->tuple.base.type, attr);
+        size_t id = mp_obj_namedtuple_find_field((mp_obj_namedtuple_type_t*)self->tuple.base.type, attr);
         if (id == (size_t)-1) {
             return;
         }
@@ -128,7 +119,7 @@ STATIC mp_obj_t namedtuple_make_new(const mp_obj_type_t *type_in, size_t n_args,
     memset(&tuple->items[n_args], 0, sizeof(mp_obj_t) * n_kw);
     for (size_t i = n_args; i < n_args + 2 * n_kw; i += 2) {
         qstr kw = mp_obj_str_get_qstr(args[i]);
-        size_t id = namedtuple_find_field(type, kw);
+        size_t id = mp_obj_namedtuple_find_field(type, kw);
         if (id == (size_t)-1) {
             if (MICROPY_ERROR_REPORTING == MICROPY_ERROR_REPORTING_TERSE) {
                 mp_arg_error_terse_mismatch();
@@ -151,9 +142,18 @@ STATIC mp_obj_t namedtuple_make_new(const mp_obj_type_t *type_in, size_t n_args,
     return MP_OBJ_FROM_PTR(tuple);
 }
 
-STATIC mp_obj_t mp_obj_new_namedtuple_type(qstr name, size_t n_fields, mp_obj_t *fields) {
+mp_obj_namedtuple_type_t *mp_obj_new_namedtuple_base(size_t n_fields, mp_obj_t *fields) {
     mp_obj_namedtuple_type_t *o = m_new_obj_var(mp_obj_namedtuple_type_t, qstr, n_fields);
     memset(&o->base, 0, sizeof(o->base));
+    o->n_fields = n_fields;
+    for (size_t i = 0; i < n_fields; i++) {
+        o->fields[i] = mp_obj_str_get_qstr(fields[i]);
+    }
+    return o;
+}
+
+STATIC mp_obj_t mp_obj_new_namedtuple_type(qstr name, size_t n_fields, mp_obj_t *fields) {
+    mp_obj_namedtuple_type_t *o = mp_obj_new_namedtuple_base(n_fields, fields);
     o->base.base.type = &mp_type_type;
     o->base.name = name;
     o->base.print = namedtuple_print;
@@ -164,10 +164,6 @@ STATIC mp_obj_t mp_obj_new_namedtuple_type(qstr name, size_t n_fields, mp_obj_t
     o->base.subscr = mp_obj_tuple_subscr;
     o->base.getiter = mp_obj_tuple_getiter;
     o->base.parent = &mp_type_tuple;
-    o->n_fields = n_fields;
-    for (size_t i = 0; i < n_fields; i++) {
-        o->fields[i] = mp_obj_str_get_qstr(fields[i]);
-    }
     return MP_OBJ_FROM_PTR(o);
 }
 

py/objnamedtuple.h

@@ -0,0 +1,44 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2014-2017 Paul Sokolovsky
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#ifndef MICROPY_INCLUDED_PY_OBJNAMEDTUPLE_H
+#define MICROPY_INCLUDED_PY_OBJNAMEDTUPLE_H
+
+#include "py/objtuple.h"
+
+typedef struct _mp_obj_namedtuple_type_t {
+    mp_obj_type_t base;
+    size_t n_fields;
+    qstr fields[];
+} mp_obj_namedtuple_type_t;
+
+typedef struct _mp_obj_namedtuple_t {
+    mp_obj_tuple_t tuple;
+} mp_obj_namedtuple_t;
+
+size_t mp_obj_namedtuple_find_field(const mp_obj_namedtuple_type_t *type, qstr name);
+mp_obj_namedtuple_type_t *mp_obj_new_namedtuple_base(size_t n_fields, mp_obj_t *fields);
+
+#endif // MICROPY_INCLUDED_PY_OBJNAMEDTUPLE_H