diff options
| -rw-r--r-- | Lib/sets.py | 54 |
1 files changed, 40 insertions, 14 deletions
diff --git a/Lib/sets.py b/Lib/sets.py index eeef0e8..fee06d7 100644 --- a/Lib/sets.py +++ b/Lib/sets.py @@ -53,7 +53,7 @@ what's tested is actually `z in y'. # and cleaned up the docstrings. # # - Raymond Hettinger added a number of speedups and other -# bugs^H^H^H^Himprovements. +# improvements. __all__ = ['BaseSet', 'Set', 'ImmutableSet'] @@ -155,26 +155,35 @@ class BaseSet(object): data[deepcopy(elt, memo)] = value return result - # Standard set operations: union, intersection, both differences + # Standard set operations: union, intersection, both differences. + # Each has an operator version (e.g. __or__, invoked with |) and a + # method version (e.g. union). - def union(self, other): + def __or__(self, other): """Return the union of two sets as a new set. (I.e. all elements that are in either set.) """ - self._binary_sanity_check(other) + if not isinstance(other, BaseSet): + return NotImplemented result = self.__class__(self._data) result._data.update(other._data) return result - __or__ = union + def union(self, other): + """Return the union of two sets as a new set. - def intersection(self, other): + (I.e. all elements that are in either set.) + """ + return self | other + + def __and__(self, other): """Return the intersection of two sets as a new set. (I.e. all elements that are in both sets.) """ - self._binary_sanity_check(other) + if not isinstance(other, BaseSet): + return NotImplemented if len(self) <= len(other): little, big = self, other else: @@ -187,14 +196,20 @@ class BaseSet(object): data[elt] = value return result - __and__ = intersection + def intersection(self, other): + """Return the intersection of two sets as a new set. - def symmetric_difference(self, other): + (I.e. all elements that are in both sets.) + """ + return self & other + + def __xor__(self, other): """Return the symmetric difference of two sets as a new set. (I.e. all elements that are in exactly one of the sets.) """ - self._binary_sanity_check(other) + if not isinstance(other, BaseSet): + return NotImplemented result = self.__class__([]) data = result._data value = True @@ -206,14 +221,20 @@ class BaseSet(object): data[elt] = value return result - __xor__ = symmetric_difference + def symmetric_difference(self, other): + """Return the symmetric difference of two sets as a new set. - def difference(self, other): + (I.e. all elements that are in exactly one of the sets.) + """ + return self ^ other + + def __sub__(self, other): """Return the difference of two sets as a new Set. (I.e. all elements that are in this set and not in the other.) """ - self._binary_sanity_check(other) + if not isinstance(other, BaseSet): + return NotImplemented result = self.__class__([]) data = result._data value = True @@ -222,7 +243,12 @@ class BaseSet(object): data[elt] = value return result - __sub__ = difference + def difference(self, other): + """Return the difference of two sets as a new Set. + + (I.e. all elements that are in this set and not in the other.) + """ + return self - other # Membership test |