mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-11-24 20:30:18 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 10

Issue 3501: Make heapq support both __le__ and __lt__.

Browse source
This commit is contained in:
Raymond Hettinger 2008-06-06 21:47:51 +00:00
parent 0d236eb05a
commit ec2fe78d47
1 changed files with 28 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

39
Modules/_heapqmodule.c
View file

@ -8,6 +8,25 @@ annotated by Fran
#include "Python.h" #include "Python.h"
/* Older implementations of heapq used Py_LE for comparisons. Now, it uses
Py_LT so it will match min(), sorted(), and bisect(). Unfortunately, some
client code (Twisted for example) relied on Py_LE, so this little function
restores compatability by trying both.
*/
static int
cmp_lt(PyObject *x, PyObject *y)
{
int cmp;
cmp = PyObject_RichCompareBool(x, y, Py_LT);
if (cmp == -1 && PyErr_ExceptionMatches(PyExc_AttributeError)) {
PyErr_Clear();
cmp = PyObject_RichCompareBool(y, x, Py_LE);
if (cmp != -1)
cmp = 1 - cmp;
}
return cmp;
}
static int static int
_siftdown(PyListObject *heap, Py_ssize_t startpos, Py_ssize_t pos) _siftdown(PyListObject *heap, Py_ssize_t startpos, Py_ssize_t pos)
{ {
@ -28,7 +47,7 @@ _siftdown(PyListObject *heap, Py_ssize_t startpos, Py_ssize_t pos)
while (pos > startpos){ while (pos > startpos){
parentpos = (pos - 1) >> 1; parentpos = (pos - 1) >> 1;
parent = PyList_GET_ITEM(heap, parentpos); parent = PyList_GET_ITEM(heap, parentpos);
cmp = PyObject_RichCompareBool(newitem, parent, Py_LT); cmp = cmp_lt(newitem, parent);
if (cmp == -1) { if (cmp == -1) {
Py_DECREF(newitem); Py_DECREF(newitem);
return -1; return -1;
@ -68,10 +87,9 @@ _siftup(PyListObject *heap, Py_ssize_t pos)
/* Set childpos to index of smaller child. */ /* Set childpos to index of smaller child. */
rightpos = childpos + 1; rightpos = childpos + 1;
if (rightpos < endpos) { if (rightpos < endpos) {
cmp = PyObject_RichCompareBool( cmp = cmp_lt(
PyList_GET_ITEM(heap, childpos), PyList_GET_ITEM(heap, childpos),
PyList_GET_ITEM(heap, rightpos), PyList_GET_ITEM(heap, rightpos));
Py_LT);
if (cmp == -1) { if (cmp == -1) {
Py_DECREF(newitem); Py_DECREF(newitem);
return -1; return -1;
@ -214,7 +232,7 @@ heappushpop(PyObject *self, PyObject *args)
return item; return item;
} }
cmp = PyObject_RichCompareBool(PyList_GET_ITEM(heap, 0), item, Py_LT); cmp = cmp_lt(PyList_GET_ITEM(heap, 0), item);
if (cmp == -1) if (cmp == -1)
return NULL; return NULL;
if (cmp == 0) { if (cmp == 0) {
@ -313,7 +331,7 @@ nlargest(PyObject *self, PyObject *args)
else else
goto sortit; goto sortit;
} }
cmp = PyObject_RichCompareBool(sol, elem, Py_LT); cmp = cmp_lt(sol, elem);
if (cmp == -1) { if (cmp == -1) {
Py_DECREF(elem); Py_DECREF(elem);
goto fail; goto fail;
@ -368,7 +386,7 @@ _siftdownmax(PyListObject *heap, Py_ssize_t startpos, Py_ssize_t pos)
while (pos > startpos){ while (pos > startpos){
parentpos = (pos - 1) >> 1; parentpos = (pos - 1) >> 1;
parent = PyList_GET_ITEM(heap, parentpos); parent = PyList_GET_ITEM(heap, parentpos);
cmp = PyObject_RichCompareBool(parent, newitem, Py_LT); cmp = cmp_lt(parent, newitem);
if (cmp == -1) { if (cmp == -1) {
Py_DECREF(newitem); Py_DECREF(newitem);
return -1; return -1;
@ -408,10 +426,9 @@ _siftupmax(PyListObject *heap, Py_ssize_t pos)
/* Set childpos to index of smaller child. */ /* Set childpos to index of smaller child. */
rightpos = childpos + 1; rightpos = childpos + 1;
if (rightpos < endpos) { if (rightpos < endpos) {
cmp = PyObject_RichCompareBool( cmp = cmp_lt(
PyList_GET_ITEM(heap, rightpos), PyList_GET_ITEM(heap, rightpos),
PyList_GET_ITEM(heap, childpos), PyList_GET_ITEM(heap, childpos));
Py_LT);
if (cmp == -1) { if (cmp == -1) {
Py_DECREF(newitem); Py_DECREF(newitem);
return -1; return -1;
@ -484,7 +501,7 @@ nsmallest(PyObject *self, PyObject *args)
else else
goto sortit; goto sortit;
} }
cmp = PyObject_RichCompareBool(elem, los, Py_LT); cmp = cmp_lt(elem, los);
if (cmp == -1) { if (cmp == -1) {
Py_DECREF(elem); Py_DECREF(elem);
goto fail; goto fail;