cpython/Lib/UserDict.py

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"""A more or less complete user-defined wrapper around dictionary objects."""
class UserDict:
def __init__(self, dict=None, **kwargs):
self.data = {}
if dict is not None:
self.update(dict)
if len(kwargs):
self.update(kwargs)
def __repr__(self): return repr(self.data)
Restructure comparison dramatically. There is no longer a default *ordering* between objects; there is only a default equality test (defined by an object being equal to itself only). Read the comment in object.c. The current implementation never uses a three-way comparison to compute a rich comparison, but it does use a rich comparison to compute a three-way comparison. I'm not quite done ripping out all the calls to PyObject_Compare/Cmp, or replacing tp_compare implementations with tp_richcompare implementations; but much of that has happened (to make most unit tests pass). The following tests still fail, because I need help deciding or understanding: test_codeop -- depends on comparing code objects test_datetime -- need Tim Peters' opinion test_marshal -- depends on comparing code objects test_mutants -- need help understanding it The problem with test_codeop and test_marshal is this: these tests compare two different code objects and expect them to be equal. Is that still a feature we'd like to support? I've temporarily removed the comparison and hash code from code objects, so they use the default (equality by pointer only) comparison. For the other two tests, run them to see for yourself. (There may be more failing test with "-u all".) A general problem with getting lots of these tests to pass is the reality that for object types that have a natural total ordering, implementing __cmp__ is much more convenient than implementing __eq__, __ne__, __lt__, and so on. Should we go back to allowing __cmp__ to provide a total ordering? Should we provide some other way to implement rich comparison with a single method override? Alex proposed a __key__() method; I've considered a __richcmp__() method. Or perhaps __cmp__() just shouldn't be killed off...
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def __eq__(self, dict):
if isinstance(dict, UserDict):
Restructure comparison dramatically. There is no longer a default *ordering* between objects; there is only a default equality test (defined by an object being equal to itself only). Read the comment in object.c. The current implementation never uses a three-way comparison to compute a rich comparison, but it does use a rich comparison to compute a three-way comparison. I'm not quite done ripping out all the calls to PyObject_Compare/Cmp, or replacing tp_compare implementations with tp_richcompare implementations; but much of that has happened (to make most unit tests pass). The following tests still fail, because I need help deciding or understanding: test_codeop -- depends on comparing code objects test_datetime -- need Tim Peters' opinion test_marshal -- depends on comparing code objects test_mutants -- need help understanding it The problem with test_codeop and test_marshal is this: these tests compare two different code objects and expect them to be equal. Is that still a feature we'd like to support? I've temporarily removed the comparison and hash code from code objects, so they use the default (equality by pointer only) comparison. For the other two tests, run them to see for yourself. (There may be more failing test with "-u all".) A general problem with getting lots of these tests to pass is the reality that for object types that have a natural total ordering, implementing __cmp__ is much more convenient than implementing __eq__, __ne__, __lt__, and so on. Should we go back to allowing __cmp__ to provide a total ordering? Should we provide some other way to implement rich comparison with a single method override? Alex proposed a __key__() method; I've considered a __richcmp__() method. Or perhaps __cmp__() just shouldn't be killed off...
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return self.data == dict.data
else:
Restructure comparison dramatically. There is no longer a default *ordering* between objects; there is only a default equality test (defined by an object being equal to itself only). Read the comment in object.c. The current implementation never uses a three-way comparison to compute a rich comparison, but it does use a rich comparison to compute a three-way comparison. I'm not quite done ripping out all the calls to PyObject_Compare/Cmp, or replacing tp_compare implementations with tp_richcompare implementations; but much of that has happened (to make most unit tests pass). The following tests still fail, because I need help deciding or understanding: test_codeop -- depends on comparing code objects test_datetime -- need Tim Peters' opinion test_marshal -- depends on comparing code objects test_mutants -- need help understanding it The problem with test_codeop and test_marshal is this: these tests compare two different code objects and expect them to be equal. Is that still a feature we'd like to support? I've temporarily removed the comparison and hash code from code objects, so they use the default (equality by pointer only) comparison. For the other two tests, run them to see for yourself. (There may be more failing test with "-u all".) A general problem with getting lots of these tests to pass is the reality that for object types that have a natural total ordering, implementing __cmp__ is much more convenient than implementing __eq__, __ne__, __lt__, and so on. Should we go back to allowing __cmp__ to provide a total ordering? Should we provide some other way to implement rich comparison with a single method override? Alex proposed a __key__() method; I've considered a __richcmp__() method. Or perhaps __cmp__() just shouldn't be killed off...
2006-08-23 21:41:19 -03:00
return self.data == dict
def __ne__(self, dict):
if isinstance(dict, UserDict):
return self.data != dict.data
else:
return self.data != dict
def __len__(self): return len(self.data)
def __getitem__(self, key):
if key in self.data:
return self.data[key]
if hasattr(self.__class__, "__missing__"):
return self.__class__.__missing__(self, key)
raise KeyError(key)
def __setitem__(self, key, item): self.data[key] = item
def __delitem__(self, key): del self.data[key]
def clear(self): self.data.clear()
def copy(self):
if self.__class__ is UserDict:
return UserDict(self.data.copy())
import copy
data = self.data
try:
self.data = {}
c = copy.copy(self)
finally:
self.data = data
c.update(self)
return c
def keys(self): return self.data.keys()
def items(self): return self.data.items()
def values(self): return self.data.values()
def update(self, dict=None, **kwargs):
if dict is None:
pass
elif isinstance(dict, UserDict):
self.data.update(dict.data)
elif isinstance(dict, type({})) or not hasattr(dict, 'items'):
self.data.update(dict)
else:
for k, v in dict.items():
self[k] = v
if len(kwargs):
self.data.update(kwargs)
def get(self, key, failobj=None):
if key not in self:
return failobj
return self[key]
def setdefault(self, key, failobj=None):
if key not in self:
self[key] = failobj
return self[key]
def pop(self, key, *args):
return self.data.pop(key, *args)
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def popitem(self):
return self.data.popitem()
def __contains__(self, key):
return key in self.data
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@classmethod
def fromkeys(cls, iterable, value=None):
d = cls()
for key in iterable:
d[key] = value
return d
class IterableUserDict(UserDict):
def __iter__(self):
return iter(self.data)
class DictMixin:
# Mixin defining all dictionary methods for classes that already have
# a minimum dictionary interface including getitem, setitem, delitem,
# and keys. Without knowledge of the subclass constructor, the mixin
# does not define __init__() or copy(). In addition to the four base
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# methods, progressively more efficiency comes with defining
# __contains__(), __iter__(), and iteritems().
# XXX It would make more sense to expect __iter__ to be primitive.
# second level definitions support higher levels
def __iter__(self):
for k in self.keys():
yield k
def __contains__(self, key):
try:
value = self[key]
except KeyError:
return False
return True
# third level takes advantage of second level definitions
def iterkeys(self):
return self.__iter__()
def iteritems(self):
for k in self:
yield (k, self[k])
# fourth level uses definitions from lower levels
def itervalues(self):
for _, v in self.iteritems():
yield v
def values(self):
return [v for _, v in self.iteritems()]
def items(self):
return list(self.iteritems())
def clear(self):
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for key in list(self.iterkeys()):
del self[key]
def setdefault(self, key, default=None):
try:
return self[key]
except KeyError:
self[key] = default
return default
def pop(self, key, *args):
if len(args) > 1:
raise TypeError, "pop expected at most 2 arguments, got "\
+ repr(1 + len(args))
try:
value = self[key]
except KeyError:
if args:
return args[0]
raise
del self[key]
return value
def popitem(self):
try:
k, v = next(self.iteritems())
except StopIteration:
raise KeyError, 'container is empty'
del self[k]
return (k, v)
def update(self, other=None, **kwargs):
# Make progressively weaker assumptions about "other"
if other is None:
pass
elif hasattr(other, 'iteritems'): # iteritems saves memory and lookups
for k, v in other.iteritems():
self[k] = v
elif hasattr(other, 'items'): # items may also save memory and lookups
for k, v in other.items():
self[k] = v
elif hasattr(other, 'keys'):
for k in other.keys():
self[k] = other[k]
else:
for k, v in other:
self[k] = v
if kwargs:
self.update(kwargs)
def get(self, key, default=None):
try:
return self[key]
except KeyError:
return default
def __repr__(self):
return repr(dict(self.iteritems()))
Restructure comparison dramatically. There is no longer a default *ordering* between objects; there is only a default equality test (defined by an object being equal to itself only). Read the comment in object.c. The current implementation never uses a three-way comparison to compute a rich comparison, but it does use a rich comparison to compute a three-way comparison. I'm not quite done ripping out all the calls to PyObject_Compare/Cmp, or replacing tp_compare implementations with tp_richcompare implementations; but much of that has happened (to make most unit tests pass). The following tests still fail, because I need help deciding or understanding: test_codeop -- depends on comparing code objects test_datetime -- need Tim Peters' opinion test_marshal -- depends on comparing code objects test_mutants -- need help understanding it The problem with test_codeop and test_marshal is this: these tests compare two different code objects and expect them to be equal. Is that still a feature we'd like to support? I've temporarily removed the comparison and hash code from code objects, so they use the default (equality by pointer only) comparison. For the other two tests, run them to see for yourself. (There may be more failing test with "-u all".) A general problem with getting lots of these tests to pass is the reality that for object types that have a natural total ordering, implementing __cmp__ is much more convenient than implementing __eq__, __ne__, __lt__, and so on. Should we go back to allowing __cmp__ to provide a total ordering? Should we provide some other way to implement rich comparison with a single method override? Alex proposed a __key__() method; I've considered a __richcmp__() method. Or perhaps __cmp__() just shouldn't be killed off...
2006-08-23 21:41:19 -03:00
def __eq__(self, other):
if isinstance(other, DictMixin):
other = dict(other.iteritems())
return dict(self.iteritems()) == other
Restructure comparison dramatically. There is no longer a default *ordering* between objects; there is only a default equality test (defined by an object being equal to itself only). Read the comment in object.c. The current implementation never uses a three-way comparison to compute a rich comparison, but it does use a rich comparison to compute a three-way comparison. I'm not quite done ripping out all the calls to PyObject_Compare/Cmp, or replacing tp_compare implementations with tp_richcompare implementations; but much of that has happened (to make most unit tests pass). The following tests still fail, because I need help deciding or understanding: test_codeop -- depends on comparing code objects test_datetime -- need Tim Peters' opinion test_marshal -- depends on comparing code objects test_mutants -- need help understanding it The problem with test_codeop and test_marshal is this: these tests compare two different code objects and expect them to be equal. Is that still a feature we'd like to support? I've temporarily removed the comparison and hash code from code objects, so they use the default (equality by pointer only) comparison. For the other two tests, run them to see for yourself. (There may be more failing test with "-u all".) A general problem with getting lots of these tests to pass is the reality that for object types that have a natural total ordering, implementing __cmp__ is much more convenient than implementing __eq__, __ne__, __lt__, and so on. Should we go back to allowing __cmp__ to provide a total ordering? Should we provide some other way to implement rich comparison with a single method override? Alex proposed a __key__() method; I've considered a __richcmp__() method. Or perhaps __cmp__() just shouldn't be killed off...
2006-08-23 21:41:19 -03:00
def __ne__(self, other):
if isinstance(other, DictMixin):
other = dict(other.iteritems())
return dict(self.iteritems()) != other
def __len__(self):
return len(self.keys())