Iterator support: made the xreadlines object its own iterator. This

ought to be faster.

diff --git a/Modules/xreadlinesmodule.c b/Modules/xreadlinesmodule.c
index db9e243a3ec84f177afea6d23dc2b73938d50ac8..7ae949e0df37c3eafe65b3172a4b8b529858e752 100644 (file)
--- a/Modules/xreadlinesmodule.c
+++ b/Modules/xreadlinesmodule.c
@@ -54,13 +54,8 @@ xreadlines(PyObject *self, PyObject *args)
 }
 
 static PyObject *
-xreadlines_item(PyXReadlinesObject *a, int i)
+xreadlines_common(PyXReadlinesObject *a)
 {
-       if (i != a->abslineno) {
-               PyErr_SetString(PyExc_RuntimeError,
-                       "xreadlines object accessed out of order");
-               return NULL;
-       }
        if (a->lineno >= a->lineslen) {
                Py_XDECREF(a->lines);
                a->lines = PyObject_CallMethod(a->file, "readlines", "(i)",
@@ -75,6 +70,61 @@ xreadlines_item(PyXReadlinesObject *a, int i)
        return PySequence_GetItem(a->lines, a->lineno++);
 }
 
+static PyObject *
+xreadlines_item(PyXReadlinesObject *a, int i)
+{
+       if (i != a->abslineno) {
+               PyErr_SetString(PyExc_RuntimeError,
+                       "xreadlines object accessed out of order");
+               return NULL;
+       }
+       return xreadlines_common(a);
+}
+
+static PyObject *
+xreadlines_getiter(PyXReadlinesObject *a)
+{
+       Py_INCREF(a);
+       return (PyObject *)a;
+}
+
+static PyObject *
+xreadlines_iternext(PyXReadlinesObject *a)
+{
+       PyObject *res;
+
+       res = xreadlines_common(a);
+       if (res == NULL && PyErr_ExceptionMatches(PyExc_IndexError))
+               PyErr_Clear();
+       return res;
+}
+
+static PyObject *
+xreadlines_next(PyXReadlinesObject *a, PyObject *args)
+{
+       PyObject *res;
+
+       if (!PyArg_ParseTuple(args, ""))
+               return NULL;
+       res = xreadlines_common(a);
+       if (res == NULL && PyErr_ExceptionMatches(PyExc_IndexError))
+               PyErr_SetObject(PyExc_StopIteration, Py_None);
+       return res;
+}
+
+static char next_doc[] = "x.next() -> the next line or raise StopIteration";
+
+static PyMethodDef xreadlines_methods[] = {
+       {"next", (PyCFunction)xreadlines_next, METH_VARARGS, next_doc},
+       {NULL, NULL}
+};
+
+static PyObject *
+xreadlines_getattr(PyObject *a, char *name)
+{
+       return Py_FindMethod(xreadlines_methods, a, name);
+}
+
 static PySequenceMethods xreadlines_as_sequence = {
        0, /*sq_length*/
        0, /*sq_concat*/
@@ -88,26 +138,32 @@ static PyTypeObject XReadlinesObject_Type = {
        "xreadlines",
        sizeof(PyXReadlinesObject) + PyGC_HEAD_SIZE,
        0,
-       (destructor)xreadlines_dealloc, /*tp_dealloc*/
-       0, /*tp_print*/
-       0, /*tp_getattr*/
-       0, /*tp_setattr*/
-       0, /*tp_compare*/
-       0, /*tp_repr*/
-       0, /*tp_as_number*/
-       &xreadlines_as_sequence, /*tp_as_sequence*/
-       0,              /*tp_as_mapping*/
-       0,              /*tp_hash*/
-       0,              /*tp_call*/
-       0,              /*tp_str*/
-       0,              /*tp_getattro*/
-       0,              /*tp_setattro*/
-       0,              /*tp_as_buffer*/
-       Py_TPFLAGS_DEFAULT,     /*tp_flags*/
-       0,              /* tp_doc */
+       (destructor)xreadlines_dealloc,         /* tp_dealloc */
+       0,                                      /* tp_print */
+       xreadlines_getattr,                     /* tp_getattr */
+       0,                                      /* tp_setattr */
+       0,                                      /* tp_compare */
+       0,                                      /* tp_repr */
+       0,                                      /* tp_as_number */
+       &xreadlines_as_sequence,                /* tp_as_sequence */
+       0,                                      /* tp_as_mapping */
+       0,                                      /* tp_hash */
+       0,                                      /* tp_call */
+       0,                                      /* tp_str */
+       0,                                      /* tp_getattro */
+       0,                                      /* tp_setattro */
+       0,                                      /* tp_as_buffer */
+       Py_TPFLAGS_DEFAULT,                     /* tp_flags */
+       0,                                      /* tp_doc */
+       0,                                      /* tp_traverse */
+       0,                                      /* tp_clear */
+       0,                                      /* tp_richcompare */
+       0,                                      /* tp_weaklistoffset */
+       (getiterfunc)xreadlines_getiter,        /* tp_iter */
+       (iternextfunc)xreadlines_iternext,      /* tp_iternext */
 };
 
-static PyMethodDef xreadlines_methods[] = {
+static PyMethodDef xreadlines_functions[] = {
        {"xreadlines", xreadlines, METH_VARARGS, xreadlines_doc},
        {NULL, NULL}
 };
@@ -118,5 +174,5 @@ initxreadlines(void)
        PyObject *m;
 
        XReadlinesObject_Type.ob_type = &PyType_Type;
-       m = Py_InitModule("xreadlines", xreadlines_methods);
+       m = Py_InitModule("xreadlines", xreadlines_functions);
 }