rather than the idle.py script. This has advantages and
disadvantages; the biggest advantage being that we can more easily
have an alternative main program.
Allow module getattr and setattr to exploit string interning, via the
previously null module object tp_getattro and tp_setattro slots. Yields
a very nice speedup for things like random.random and os.path etc.
When getting a string buffer for a string we just created, use
PyString_AS_STRING() instead of PyString_AsString() to avoid the
call overhead and extra type check.
For rich comparisons, use instance_getattr2() when possible to avoid
the expense of setting an AttributeError. Also intern the name_op[]
table and use the interned strings rather than creating a new string
and interning it each time through.
class without providing any information about the constructor. This
should be used for classes which only exist to act as containers rather
than as factories for instances.
doesn't know how to do LE, LT, GE, GT. dict_richcompare can't do the
latter any faster than dict_compare can. More importantly, for
cmp(dict1, dict2), Python *first* tries rich compares with EQ, LT, and
GT one at a time, even if the tp_compare slot is defined, and
dict_richcompare called dict_compare for the latter two because
it couldn't do them itself. The result was a lot of wasted calls to
dict_compare. Now dict_richcompare gives up at once the times Python
calls it with LT and GT from try_rich_to_3way_compare(), and dict_compare
is called only once (when Python gets around to trying the tp_compare
slot).
Continued mystery: despite that this cut the number of calls to
dict_compare approximately in half in test_mutants.py, the latter still
runs amazingly slowly. Running under the debugger doesn't show excessive
activity in the dict comparison code anymore, so I'm guessing the culprit
is somewhere else -- but where? Perhaps in the element (key/value)
comparison code? We clearly spend a lot of time figuring out how to
compare things.
A Mystery: test_mutants ran amazingly slowly even before dictobject.c
"got fixed". I don't have a clue as to why. dict comparison was and
remains linear-time in the size of the dicts, and test_mutants only tries
100 dict pairs, of size averaging just 50. So "it should" run in less than
an eyeblink; but it takes at least a second on this 800MHz box.
Fixed a half dozen ways in which general dict comparison could crash
Python (even cause Win98SE to reboot) in the presence of kay and/or
value comparison routines that mutate the dict during dict comparison.
Bugfix candidate.
Guido van Rossum
Tim Peters
Fred Drake
Jeremy Hylton
Jack Jansen
Steve Purcell