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Python Compiled Bytecode | 2009-11-11 | 18KB | 568 lines

# Source Generated with Decompyle++
# File: in.pyc (Python 2.6)

"""Classes to represent arbitrary sets (including sets of sets).

This module implements sets using dictionaries whose values are
ignored.  The usual operations (union, intersection, deletion, etc.)
are provided as both methods and operators.

Important: sets are not sequences!  While they support 'x in s',
'len(s)', and 'for x in s', none of those operations are unique for
sequences; for example, mappings support all three as well.  The
characteristic operation for sequences is subscripting with small
integers: s[i], for i in range(len(s)).  Sets don't support
subscripting at all.  Also, sequences allow multiple occurrences and
their elements have a definite order; sets on the other hand don't
record multiple occurrences and don't remember the order of element
insertion (which is why they don't support s[i]).

The following classes are provided:

BaseSet -- All the operations common to both mutable and immutable
    sets. This is an abstract class, not meant to be directly
    instantiated.

Set -- Mutable sets, subclass of BaseSet; not hashable.

ImmutableSet -- Immutable sets, subclass of BaseSet; hashable.
    An iterable argument is mandatory to create an ImmutableSet.

_TemporarilyImmutableSet -- A wrapper around a Set, hashable,
    giving the same hash value as the immutable set equivalent
    would have.  Do not use this class directly.

Only hashable objects can be added to a Set. In particular, you cannot
really add a Set as an element to another Set; if you try, what is
actually added is an ImmutableSet built from it (it compares equal to
the one you tried adding).

When you ask if `x in y' where x is a Set and y is a Set or
ImmutableSet, x is wrapped into a _TemporarilyImmutableSet z, and
what's tested is actually `z in y'.

"""
from __future__ import generators

try:
    from itertools import ifilter, ifilterfalse
except ImportError:

    def ifilter(predicate, iterable):
        if predicate is None:

            def predicate(x):
                return x


        for x in iterable:
            if predicate(x):
                yield x
                continue



    def ifilterfalse(predicate, iterable):
        if predicate is None:

            def predicate(x):
                return x


        for x in iterable:
            if not predicate(x):
                yield x
                continue



    try:
        (True, False)
    except NameError:
        (True, False) = (0 == 0, 0 != 0)


__all__ = [
    'BaseSet',
    'Set',
    'ImmutableSet']
import warnings
warnings.warn('the sets module is deprecated', DeprecationWarning, stacklevel = 2)

class BaseSet(object):
    '''Common base class for mutable and immutable sets.'''
    __slots__ = [
        '_data']

    def __init__(self):
        '''This is an abstract class.'''
        if self.__class__ is BaseSet:
            raise TypeError, 'BaseSet is an abstract class.  Use Set or ImmutableSet.'
        self.__class__ is BaseSet


    def __len__(self):
        '''Return the number of elements of a set.'''
        return len(self._data)


    def __repr__(self):
        """Return string representation of a set.

        This looks like 'Set([<list of elements>])'.
        """
        return self._repr()

    __str__ = __repr__

    def _repr(self, sorted = False):
        elements = self._data.keys()
        if sorted:
            elements.sort()

        return '%s(%r)' % (self.__class__.__name__, elements)


    def __iter__(self):
        '''Return an iterator over the elements or a set.

        This is the keys iterator for the underlying dict.
        '''
        return self._data.iterkeys()


    def __cmp__(self, other):
        raise TypeError, "can't compare sets using cmp()"


    def __eq__(self, other):
        if isinstance(other, BaseSet):
            return self._data == other._data
        return False


    def __ne__(self, other):
        if isinstance(other, BaseSet):
            return self._data != other._data
        return True


    def copy(self):
        '''Return a shallow copy of a set.'''
        result = self.__class__()
        result._data.update(self._data)
        return result

    __copy__ = copy

    def __deepcopy__(self, memo):
        '''Return a deep copy of a set; used by copy module.'''
        deepcopy = deepcopy
        import copy
        result = self.__class__()
        memo[id(self)] = result
        data = result._data
        value = True
        for elt in self:
            data[deepcopy(elt, memo)] = value

        return result


    def __or__(self, other):
        '''Return the union of two sets as a new set.

        (I.e. all elements that are in either set.)
        '''
        if not isinstance(other, BaseSet):
            return NotImplemented
        return self.union(other)


    def union(self, other):
        '''Return the union of two sets as a new set.

        (I.e. all elements that are in either set.)
        '''
        result = self.__class__(self)
        result._update(other)
        return result


    def __and__(self, other):
        '''Return the intersection of two sets as a new set.

        (I.e. all elements that are in both sets.)
        '''
        if not isinstance(other, BaseSet):
            return NotImplemented
        return self.intersection(other)


    def intersection(self, other):
        '''Return the intersection of two sets as a new set.

        (I.e. all elements that are in both sets.)
        '''
        if not isinstance(other, BaseSet):
            other = Set(other)

        if len(self) <= len(other):
            little = self
            big = other
        else:
            little = other
            big = self
        common = ifilter(big._data.has_key, little)
        return self.__class__(common)


    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.)
        '''
        if not isinstance(other, BaseSet):
            return NotImplemented
        return self.symmetric_difference(other)


    def symmetric_difference(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.)
        '''
        result = self.__class__()
        data = result._data
        value = True
        selfdata = self._data

        try:
            otherdata = other._data
        except AttributeError:
            otherdata = Set(other)._data

        for elt in ifilterfalse(otherdata.has_key, selfdata):
            data[elt] = value

        for elt in ifilterfalse(selfdata.has_key, otherdata):
            data[elt] = value

        return result


    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.)
        '''
        if not isinstance(other, BaseSet):
            return NotImplemented
        return self.difference(other)


    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.)
        '''
        result = self.__class__()
        data = result._data

        try:
            otherdata = other._data
        except AttributeError:
            otherdata = Set(other)._data

        value = True
        for elt in ifilterfalse(otherdata.has_key, self):
            data[elt] = value

        return result


    def __contains__(self, element):
        """Report whether an element is a member of a set.

        (Called in response to the expression `element in self'.)
        """

        try:
            return element in self._data
        except TypeError:
            transform = getattr(element, '__as_temporarily_immutable__', None)
            if transform is None:
                raise
            transform is None
            return transform() in self._data



    def issubset(self, other):
        '''Report whether another set contains this set.'''
        self._binary_sanity_check(other)
        if len(self) > len(other):
            return False
        for elt in ifilterfalse(other._data.has_key, self):
            return False

        return True


    def issuperset(self, other):
        '''Report whether this set contains another set.'''
        self._binary_sanity_check(other)
        if len(self) < len(other):
            return False
        for elt in ifilterfalse(self._data.has_key, other):
            return False

        return True

    __le__ = issubset
    __ge__ = issuperset

    def __lt__(self, other):
        self._binary_sanity_check(other)
        if len(self) < len(other):
            pass
        return self.issubset(other)


    def __gt__(self, other):
        self._binary_sanity_check(other)
        if len(self) > len(other):
            pass
        return self.issuperset(other)


    def _binary_sanity_check(self, other):
        if not isinstance(other, BaseSet):
            raise TypeError, 'Binary operation only permitted between sets'
        isinstance(other, BaseSet)


    def _compute_hash(self):
        result = 0
        for elt in self:
            result ^= hash(elt)

        return result


    def _update(self, iterable):
        data = self._data
        if isinstance(iterable, BaseSet):
            data.update(iterable._data)
            return None
        value = True



class ImmutableSet(BaseSet):
    '''Immutable set class.'''
    __slots__ = [
        '_hashcode']

    def __init__(self, iterable = None):
        '''Construct an immutable set from an optional iterable.'''
        self._hashcode = None
        self._data = { }
        if iterable is not None:
            self._update(iterable)



    def __hash__(self):
        if self._hashcode is None:
            self._hashcode = self._compute_hash()

        return self._hashcode


    def __getstate__(self):
        return (self._data, self._hashcode)


    def __setstate__(self, state):
        (self._data, self._hashcode) = state



class Set(BaseSet):
    ''' Mutable set class.'''
    __slots__ = []

    def __init__(self, iterable = None):
        '''Construct a set from an optional iterable.'''
        self._data = { }
        if iterable is not None:
            self._update(iterable)



    def __getstate__(self):
        return (self._data,)


    def __setstate__(self, data):
        (self._data,) = data

    __hash__ = None

    def __ior__(self, other):
        '''Update a set with the union of itself and another.'''
        self._binary_sanity_check(other)
        self._data.update(other._data)
        return self


    def union_update(self, other):
        '''Update a set with the union of itself and another.'''
        self._update(other)


    def __iand__(self, other):
        '''Update a set with the intersection of itself and another.'''
        self._binary_sanity_check(other)
        self._data = (self & other)._data
        return self


    def intersection_update(self, other):
        '''Update a set with the intersection of itself and another.'''
        if isinstance(other, BaseSet):
            self &= other
        else:
            self._data = self.intersection(other)._data


    def __ixor__(self, other):
        '''Update a set with the symmetric difference of itself and another.'''
        self._binary_sanity_check(other)
        self.symmetric_difference_update(other)
        return self


    def symmetric_difference_update(self, other):
        '''Update a set with the symmetric difference of itself and another.'''
        data = self._data
        value = True
        if not isinstance(other, BaseSet):
            other = Set(other)

        if self is other:
            self.clear()

        for elt in other:
            if elt in data:
                del data[elt]
                continue
            data[elt] = value



    def __isub__(self, other):
        '''Remove all elements of another set from this set.'''
        self._binary_sanity_check(other)
        self.difference_update(other)
        return self


    def difference_update(self, other):
        '''Remove all elements of another set from this set.'''
        data = self._data
        if not isinstance(other, BaseSet):
            other = Set(other)

        if self is other:
            self.clear()

        for elt in ifilter(data.has_key, other):
            del data[elt]



    def update(self, iterable):
        '''Add all values from an iterable (such as a list or file).'''
        self._update(iterable)


    def clear(self):
        '''Remove all elements from this set.'''
        self._data.clear()


    def add(self, element):
        '''Add an element to a set.

        This has no effect if the element is already present.
        '''

        try:
            self._data[element] = True
        except TypeError:
            transform = getattr(element, '__as_immutable__', None)
            if transform is None:
                raise
            transform is None
            self._data[transform()] = True



    def remove(self, element):
        '''Remove an element from a set; it must be a member.

        If the element is not a member, raise a KeyError.
        '''

        try:
            del self._data[element]
        except TypeError:
            transform = getattr(element, '__as_temporarily_immutable__', None)
            if transform is None:
                raise
            transform is None
            del self._data[transform()]



    def discard(self, element):
        '''Remove an element from a set if it is a member.

        If the element is not a member, do nothing.
        '''

        try:
            self.remove(element)
        except KeyError:
            pass



    def pop(self):
        '''Remove and return an arbitrary set element.'''
        return self._data.popitem()[0]


    def __as_immutable__(self):
        return ImmutableSet(self)


    def __as_temporarily_immutable__(self):
        return _TemporarilyImmutableSet(self)



class _TemporarilyImmutableSet(BaseSet):

    def __init__(self, set):
        self._set = set
        self._data = set._data


    def __hash__(self):
        return self._set._compute_hash()