diff options
Diffstat (limited to 'py/objstr.c')
| -rw-r--r-- | py/objstr.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/py/objstr.c b/py/objstr.c index 48abf4951d..59547e3cd6 100644 --- a/py/objstr.c +++ b/py/objstr.c @@ -27,9 +27,31 @@ mp_obj_t str_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) { const char *lhs_str = qstr_str(lhs->qstr); switch (op) { case RT_BINARY_OP_SUBSCR: - // string access - // XXX a massive hack! - return mp_obj_new_int(lhs_str[mp_obj_get_int(rhs_in)]); + // TODO: need predicate to check for int-like type (bools are such for example) + // ["no", "yes"][1 == 2] is common idiom + if (MP_OBJ_IS_SMALL_INT(rhs_in)) { + // TODO: This implements byte string access for single index so far + // TODO: Handle negative indexes. + return mp_obj_new_int(lhs_str[mp_obj_get_int(rhs_in)]); +#if MICROPY_ENABLE_SLICE + } else if (MP_OBJ_IS_TYPE(rhs_in, &slice_type)) { + machine_int_t start, stop, step; + mp_obj_slice_get(rhs_in, &start, &stop, &step); + assert(step == 1); + int len = strlen(lhs_str); + if (start < 0) { + start = len + start; + } + if (stop <= 0) { + stop = len + stop; + } + return mp_obj_new_str(qstr_from_strn_copy(lhs_str + start, stop - start)); +#endif + } else { + // Message doesn't match CPython, but we don't have so much bytes as they + // to spend them on verbose wording + nlr_jump(mp_obj_new_exception_msg(rt_q_TypeError, "index must be int")); + } case RT_BINARY_OP_ADD: case RT_BINARY_OP_INPLACE_ADD: |