diff options
Diffstat (limited to 'Lib/decimal.py')
| -rw-r--r-- | Lib/decimal.py | 38 |
1 files changed, 25 insertions, 13 deletions
diff --git a/Lib/decimal.py b/Lib/decimal.py index a10bdf2502..159669c3f3 100644 --- a/Lib/decimal.py +++ b/Lib/decimal.py @@ -855,7 +855,7 @@ class Decimal(object): # that specified by IEEE 754. def __eq__(self, other): - other = _convert_other(other) + other = _convert_other(other, allow_float=True) if other is NotImplemented: return other if self.is_nan() or other.is_nan(): @@ -863,7 +863,7 @@ class Decimal(object): return self._cmp(other) == 0 def __ne__(self, other): - other = _convert_other(other) + other = _convert_other(other, allow_float=True) if other is NotImplemented: return other if self.is_nan() or other.is_nan(): @@ -871,7 +871,7 @@ class Decimal(object): return self._cmp(other) != 0 def __lt__(self, other, context=None): - other = _convert_other(other) + other = _convert_other(other, allow_float=True) if other is NotImplemented: return other ans = self._compare_check_nans(other, context) @@ -880,7 +880,7 @@ class Decimal(object): return self._cmp(other) < 0 def __le__(self, other, context=None): - other = _convert_other(other) + other = _convert_other(other, allow_float=True) if other is NotImplemented: return other ans = self._compare_check_nans(other, context) @@ -889,7 +889,7 @@ class Decimal(object): return self._cmp(other) <= 0 def __gt__(self, other, context=None): - other = _convert_other(other) + other = _convert_other(other, allow_float=True) if other is NotImplemented: return other ans = self._compare_check_nans(other, context) @@ -898,7 +898,7 @@ class Decimal(object): return self._cmp(other) > 0 def __ge__(self, other, context=None): - other = _convert_other(other) + other = _convert_other(other, allow_float=True) if other is NotImplemented: return other ans = self._compare_check_nans(other, context) @@ -932,12 +932,18 @@ class Decimal(object): # The hash of a nonspecial noninteger Decimal must depend only # on the value of that Decimal, and not on its representation. # For example: hash(Decimal('100E-1')) == hash(Decimal('10')). - if self._is_special: - if self._isnan(): - raise TypeError('Cannot hash a NaN value.') - return hash(str(self)) - if not self: - return 0 + if self._is_special and self._isnan(): + raise TypeError('Cannot hash a NaN value.') + + # In Python 2.7, we're allowing comparisons (but not + # arithmetic operations) between floats and Decimals; so if + # a Decimal instance is exactly representable as a float then + # its hash should match that of the float. Note that this takes care + # of zeros and infinities, as well as small integers. + self_as_float = float(self) + if Decimal.from_float(self_as_float) == self: + return hash(self_as_float) + if self._isinteger(): op = _WorkRep(self.to_integral_value()) # to make computation feasible for Decimals with large @@ -5695,15 +5701,21 @@ def _log10_lb(c, correction = { ##### Helper Functions #################################################### -def _convert_other(other, raiseit=False): +def _convert_other(other, raiseit=False, allow_float=False): """Convert other to Decimal. Verifies that it's ok to use in an implicit construction. + If allow_float is true, allow conversion from float; this + is used in the comparison methods (__eq__ and friends). + """ if isinstance(other, Decimal): return other if isinstance(other, (int, long)): return Decimal(other) + if allow_float and isinstance(other, float): + return Decimal.from_float(other) + if raiseit: raise TypeError("Unable to convert %s to Decimal" % other) return NotImplemented |