1/*
2 * This file is part of the MicroPython project, http://micropython.org/
3 *
4 * The MIT License (MIT)
5 *
6 * Copyright (c) 2013, 2014 Damien P. George
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26
27#include <stdlib.h>
28
29#include "py/runtime.h"
30
31// this is a wrapper object that turns something that has a __getitem__ method into an iterator
32
33typedef struct _mp_obj_getitem_iter_t {
34 mp_obj_base_t base;
35 mp_obj_t args[3];
36} mp_obj_getitem_iter_t;
37
38STATIC mp_obj_t it_iternext(mp_obj_t self_in) {
39 mp_obj_getitem_iter_t *self = MP_OBJ_TO_PTR(self_in);
40 nlr_buf_t nlr;
41 if (nlr_push(&nlr) == 0) {
42 // try to get next item
43 mp_obj_t value = mp_call_method_n_kw(1, 0, self->args);
44 self->args[2] = MP_OBJ_NEW_SMALL_INT(MP_OBJ_SMALL_INT_VALUE(self->args[2]) + 1);
45 nlr_pop();
46 return value;
47 } else {
48 // an exception was raised
49 mp_obj_type_t *t = (mp_obj_type_t *)((mp_obj_base_t *)nlr.ret_val)->type;
50 if (t == &mp_type_StopIteration || t == &mp_type_IndexError) {
51 // return MP_OBJ_STOP_ITERATION instead of raising
52 return MP_OBJ_STOP_ITERATION;
53 } else {
54 // re-raise exception
55 nlr_jump(nlr.ret_val);
56 }
57 }
58}
59
60STATIC const mp_obj_type_t mp_type_it = {
61 { &mp_type_type },
62 .name = MP_QSTR_iterator,
63 .getiter = mp_identity_getiter,
64 .iternext = it_iternext,
65};
66
67// args are those returned from mp_load_method_maybe (ie either an attribute or a method)
68mp_obj_t mp_obj_new_getitem_iter(mp_obj_t *args, mp_obj_iter_buf_t *iter_buf) {
69 assert(sizeof(mp_obj_getitem_iter_t) <= sizeof(mp_obj_iter_buf_t));
70 mp_obj_getitem_iter_t *o = (mp_obj_getitem_iter_t *)iter_buf;
71 o->base.type = &mp_type_it;
72 o->args[0] = args[0];
73 o->args[1] = args[1];
74 o->args[2] = MP_OBJ_NEW_SMALL_INT(0);
75 return MP_OBJ_FROM_PTR(o);
76}
77