PythonExtra/py/objslice.c
Damien George c5966128c7 Implement proper exception type hierarchy.
Each built-in exception is now a type, with base type BaseException.
C exceptions are created by passing a pointer to the exception type to
make an instance of.  When raising an exception from the VM, an
instance is created automatically if an exception type is raised (as
opposed to an exception instance).

Exception matching (RT_BINARY_OP_EXCEPTION_MATCH) is now proper.

Handling of parse error changed to match new exceptions.

mp_const_type renamed to mp_type_type for consistency.
2014-02-15 16:10:44 +00:00

93 lines
3 KiB
C

#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <assert.h>
#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "obj.h"
#include "runtime0.h"
/******************************************************************************/
/* ellipsis object, a singleton */
typedef struct _mp_obj_ellipsis_t {
mp_obj_base_t base;
} mp_obj_ellipsis_t;
void ellipsis_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
print(env, "Ellipsis");
}
const mp_obj_type_t ellipsis_type = {
{ &mp_type_type },
.name = MP_QSTR_Ellipsis,
.print = ellipsis_print,
};
STATIC const mp_obj_ellipsis_t ellipsis_obj = {{&ellipsis_type}};
const mp_obj_t mp_const_ellipsis = (mp_obj_t)&ellipsis_obj;
/******************************************************************************/
/* slice object */
#if MICROPY_ENABLE_SLICE
// TODO: This implements only variant of slice with 2 integer args only.
// CPython supports 3rd arg (step), plus args can be arbitrary Python objects.
typedef struct _mp_obj_slice_t {
mp_obj_base_t base;
machine_int_t start;
machine_int_t stop;
} mp_obj_slice_t;
void slice_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t o_in, mp_print_kind_t kind) {
mp_obj_slice_t *o = o_in;
print(env, "slice(" INT_FMT ", " INT_FMT ")", o->start, o->stop);
}
const mp_obj_type_t slice_type = {
{ &mp_type_type },
.name = MP_QSTR_slice,
.print = slice_print,
};
// TODO: Make sure to handle "empty" values, which are signified by None in CPython
mp_obj_t mp_obj_new_slice(mp_obj_t ostart, mp_obj_t ostop, mp_obj_t ostep) {
assert(ostep == NULL);
machine_int_t start = 0, stop = 0;
if (ostart != mp_const_none) {
start = mp_obj_get_int(ostart);
}
if (ostop != mp_const_none) {
stop = mp_obj_get_int(ostop);
if (stop == 0) {
// [x:0] is a special case - in our slice object, stop = 0 means
// "end of sequence". Fortunately, [x:0] is an empty seqence for
// any x (including negative). [x:x] is also always empty sequence.
// but x also can be 0. But note that b""[x:x] is b"" for any x (i.e.
// no IndexError, at least in Python 3.3.3). So, we just use -1's to
// signify that. -1 is catchy "special" number in case someone will
// try to print [x:0] slice ever.
start = stop = -1;
}
}
mp_obj_slice_t *o = m_new(mp_obj_slice_t, 1);
o->base.type = &slice_type;
o->start = start;
o->stop = stop;
return (mp_obj_t)o;
}
void mp_obj_slice_get(mp_obj_t self_in, machine_int_t *start, machine_int_t *stop, machine_int_t *step) {
assert(MP_OBJ_IS_TYPE(self_in, &slice_type));
mp_obj_slice_t *self = self_in;
*start = self->start;
*stop = self->stop;
*step = 1;
}
#endif