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-rw-r--r--Lib/collections/abc.py68
1 files changed, 68 insertions, 0 deletions
diff --git a/Lib/collections/abc.py b/Lib/collections/abc.py
index c23b7ddef0..7939268c99 100644
--- a/Lib/collections/abc.py
+++ b/Lib/collections/abc.py
@@ -90,6 +90,7 @@ class Iterator(Iterable):
@abstractmethod
def __next__(self):
+ 'Return the next item from the iterator. When exhausted, raise StopIteration'
raise StopIteration
def __iter__(self):
@@ -230,6 +231,7 @@ class Set(Sized, Iterable, Container):
return self._from_iterable(value for value in other if value in self)
def isdisjoint(self, other):
+ 'Return True if two sets have a null intersection.'
for value in other:
if value in self:
return False
@@ -292,6 +294,16 @@ Set.register(frozenset)
class MutableSet(Set):
+ """A mutable set is a finite, iterable container.
+
+ This class provides concrete generic implementations of all
+ methods except for __contains__, __iter__, __len__,
+ add(), and discard().
+
+ To override the comparisons (presumably for speed, as the
+ semantics are fixed), all you have to do is redefine __le__ and
+ then the other operations will automatically follow suit.
+ """
__slots__ = ()
@@ -370,11 +382,20 @@ class Mapping(Sized, Iterable, Container):
__slots__ = ()
+ """A Mapping is a generic container for associating key/value
+ pairs.
+
+ This class provides concrete generic implementations of all
+ methods except for __getitem__, __iter__, and __len__.
+
+ """
+
@abstractmethod
def __getitem__(self, key):
raise KeyError
def get(self, key, default=None):
+ 'D.get(k[,d]) -> D[k] if k in D, else d. d defaults to None.'
try:
return self[key]
except KeyError:
@@ -389,12 +410,15 @@ class Mapping(Sized, Iterable, Container):
return True
def keys(self):
+ "D.keys() -> a set-like object providing a view on D's keys"
return KeysView(self)
def items(self):
+ "D.items() -> a set-like object providing a view on D's items"
return ItemsView(self)
def values(self):
+ "D.values() -> an object providing a view on D's values"
return ValuesView(self)
def __eq__(self, other):
@@ -477,6 +501,15 @@ class MutableMapping(Mapping):
__slots__ = ()
+ """A MutableMapping is a generic container for associating
+ key/value pairs.
+
+ This class provides concrete generic implementations of all
+ methods except for __getitem__, __setitem__, __delitem__,
+ __iter__, and __len__.
+
+ """
+
@abstractmethod
def __setitem__(self, key, value):
raise KeyError
@@ -488,6 +521,9 @@ class MutableMapping(Mapping):
__marker = object()
def pop(self, key, default=__marker):
+ '''D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
+ If key is not found, d is returned if given, otherwise KeyError is raised.
+ '''
try:
value = self[key]
except KeyError:
@@ -499,6 +535,9 @@ class MutableMapping(Mapping):
return value
def popitem(self):
+ '''D.popitem() -> (k, v), remove and return some (key, value) pair
+ as a 2-tuple; but raise KeyError if D is empty.
+ '''
try:
key = next(iter(self))
except StopIteration:
@@ -508,6 +547,7 @@ class MutableMapping(Mapping):
return key, value
def clear(self):
+ 'D.clear() -> None. Remove all items from D.'
try:
while True:
self.popitem()
@@ -515,6 +555,11 @@ class MutableMapping(Mapping):
pass
def update(*args, **kwds):
+ ''' D.update([E, ]**F) -> None. Update D from mapping/iterable E and F.
+ If E present and has a .keys() method, does: for k in E: D[k] = E[k]
+ If E present and lacks .keys() method, does: for (k, v) in E: D[k] = v
+ In either case, this is followed by: for k, v in F.items(): D[k] = v
+ '''
if len(args) > 2:
raise TypeError("update() takes at most 2 positional "
"arguments ({} given)".format(len(args)))
@@ -536,6 +581,7 @@ class MutableMapping(Mapping):
self[key] = value
def setdefault(self, key, default=None):
+ 'D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D'
try:
return self[key]
except KeyError:
@@ -583,12 +629,16 @@ class Sequence(Sized, Iterable, Container):
yield self[i]
def index(self, value):
+ '''S.index(value) -> integer -- return first index of value.
+ Raises ValueError if the value is not present.
+ '''
for i, v in enumerate(self):
if v == value:
return i
raise ValueError
def count(self, value):
+ 'S.count(value) -> integer -- return number of occurrences of value'
return sum(1 for v in self if v == value)
Sequence.register(tuple)
@@ -613,6 +663,13 @@ class MutableSequence(Sequence):
__slots__ = ()
+ """All the operations on a read-only sequence.
+
+ Concrete subclasses must provide __new__ or __init__,
+ __getitem__, __setitem__, __delitem__, __len__, and insert().
+
+ """
+
@abstractmethod
def __setitem__(self, index, value):
raise IndexError
@@ -623,12 +680,15 @@ class MutableSequence(Sequence):
@abstractmethod
def insert(self, index, value):
+ 'S.insert(index, value) -- insert value before index'
raise IndexError
def append(self, value):
+ 'S.append(value) -- append value to the end of the sequence'
self.insert(len(self), value)
def clear(self):
+ 'S.clear() -> None -- remove all items from S'
try:
while True:
self.pop()
@@ -636,20 +696,28 @@ class MutableSequence(Sequence):
pass
def reverse(self):
+ 'S.reverse() -- reverse *IN PLACE*'
n = len(self)
for i in range(n//2):
self[i], self[n-i-1] = self[n-i-1], self[i]
def extend(self, values):
+ 'S.extend(iterable) -- extend sequence by appending elements from the iterable'
for v in values:
self.append(v)
def pop(self, index=-1):
+ '''S.pop([index]) -> item -- remove and return item at index (default last).
+ Raise IndexError if list is empty or index is out of range.
+ '''
v = self[index]
del self[index]
return v
def remove(self, value):
+ '''S.remove(value) -- remove first occurrence of value.
+ Raise ValueError if the value is not present.
+ '''
del self[self.index(value)]
def __iadd__(self, values):