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Editing: shelve.cpython-33.pyc
� �� f3 c @ s� d Z d d l m Z m Z d d l m Z d d l Z d d d d g Z Gd d � d e j � Z Gd d � d e j � Z Gd d � d e � Z Gd d � d e � Z d d d d d � Z d S( u� Manage shelves of pickled objects. A "shelf" is a persistent, dictionary-like object. The difference with dbm databases is that the values (not the keys!) in a shelf can be essentially arbitrary Python objects -- anything that the "pickle" module can handle. This includes most class instances, recursive data types, and objects containing lots of shared sub-objects. The keys are ordinary strings. To summarize the interface (key is a string, data is an arbitrary object): import shelve d = shelve.open(filename) # open, with (g)dbm filename -- no suffix d[key] = data # store data at key (overwrites old data if # using an existing key) data = d[key] # retrieve a COPY of the data at key (raise # KeyError if no such key) -- NOTE that this # access returns a *copy* of the entry! del d[key] # delete data stored at key (raises KeyError # if no such key) flag = key in d # true if the key exists list = d.keys() # a list of all existing keys (slow!) d.close() # close it Dependent on the implementation, closing a persistent dictionary may or may not be necessary to flush changes to disk. Normally, d[key] returns a COPY of the entry. This needs care when mutable entries are mutated: for example, if d[key] is a list, d[key].append(anitem) does NOT modify the entry d[key] itself, as stored in the persistent mapping -- it only modifies the copy, which is then immediately discarded, so that the append has NO effect whatsoever. To append an item to d[key] in a way that will affect the persistent mapping, use: data = d[key] data.append(anitem) d[key] = data To avoid the problem with mutable entries, you may pass the keyword argument writeback=True in the call to shelve.open. When you use: d = shelve.open(filename, writeback=True) then d keeps a cache of all entries you access, and writes them all back to the persistent mapping when you call d.close(). This ensures that such usage as d[key].append(anitem) works as intended. However, using keyword argument writeback=True may consume vast amount of memory for the cache, and it may make d.close() very slow, if you access many of d's entries after opening it in this way: d has no way to check which of the entries you access are mutable and/or which ones you actually mutate, so it must cache, and write back at close, all of the entries that you access. You can call d.sync() to write back all the entries in the cache, and empty the cache (d.sync() also synchronizes the persistent dictionary on disk, if feasible). i ( u Pickleru Unpickler( u BytesIONu Shelfu BsdDbShelfu DbfilenameShelfu openc B sL | Ee Z d Z d Z d d � Z e Z Z Z Z Z Z d d � Z d S( u _ClosedDictu> Marker for a closed dict. Access attempts raise a ValueError.c G s t d � � d S( Nu! invalid operation on closed shelf( u ValueError( u selfu args( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu closedE s u _ClosedDict.closedc C s d S( Nu <Closed Dictionary>( ( u self( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __repr__I s u _ClosedDict.__repr__N( u __name__u __module__u __qualname__u __doc__u closedu __iter__u __len__u __getitem__u __setitem__u __delitem__u keysu __repr__( u __locals__( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu _ClosedDictB s u _ClosedDictc B s� | Ee Z d Z d Z d d d d d � Z d d � Z d d � Z d d � Z d d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d S( u Shelfu� Base class for shelf implementations. This is initialized with a dictionary-like object. See the module's __doc__ string for an overview of the interface. u utf-8c C sF | | _ | d k r d } n | | _ | | _ i | _ | | _ d S( Ni ( u dictu Noneu _protocolu writebacku cacheu keyencoding( u selfu dictu protocolu writebacku keyencoding( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __init__T s u Shelf.__init__c c s/ x( | j j � D] } | j | j � Vq Wd S( N( u dictu keysu decodeu keyencoding( u selfu k( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __iter__^ s u Shelf.__iter__c C s t | j � S( N( u lenu dict( u self( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __len__b s u Shelf.__len__c C s | j | j � | j k S( N( u encodeu keyencodingu dict( u selfu key( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __contains__e s u Shelf.__contains__c C s' | j | j � | j k r# | | S| S( N( u encodeu keyencodingu dict( u selfu keyu default( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu geth s u Shelf.getc C st y | j | } Wn\ t k ro t | j | j | j � � } t | � j � } | j rk | | j | <n Yn X| S( N( u cacheu KeyErroru BytesIOu dictu encodeu keyencodingu Unpickleru loadu writeback( u selfu keyu valueu f( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __getitem__m s u Shelf.__getitem__c C sd | j r | | j | <n t � } t | | j � } | j | � | j � | j | j | j � <d S( N( u writebacku cacheu BytesIOu Pickleru _protocolu dumpu getvalueu dictu encodeu keyencoding( u selfu keyu valueu fu p( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __setitem__w s u Shelf.__setitem__c C s= | j | j | j � =y | j | =Wn t k r8 Yn Xd S( N( u dictu encodeu keyencodingu cacheu KeyError( u selfu key( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __delitem__ s u Shelf.__delitem__c C sh | j � y | j j � Wn t k r/ Yn Xy t � | _ Wn! t t f k rc d | _ Yn Xd S( N( u syncu dictu closeu AttributeErroru _ClosedDictu NameErroru TypeErroru None( u self( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu close� s u Shelf.closec C s! t | d � s d S| j � d S( Nu writeback( u hasattru close( u self( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __del__� s u Shelf.__del__c C s� | j rZ | j rZ d | _ x' | j j � D] \ } } | | | <q+ Wd | _ i | _ n t | j d � r| | j j � n d S( Nu syncFT( u writebacku cacheu Falseu itemsu Trueu hasattru dictu sync( u selfu keyu entry( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu sync� s u Shelf.syncNF( u __name__u __module__u __qualname__u __doc__u Noneu Falseu __init__u __iter__u __len__u __contains__u getu __getitem__u __setitem__u __delitem__u closeu __del__u sync( u __locals__( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu ShelfM s c B sk | Ee Z d Z d Z d d d d d � Z d d � Z d d � Z d d � Z d d � Z d d � Z d S( u BsdDbShelfu� Shelf implementation using the "BSD" db interface. This adds methods first(), next(), previous(), last() and set_location() that have no counterpart in [g]dbm databases. The actual database must be opened using one of the "bsddb" modules "open" routines (i.e. bsddb.hashopen, bsddb.btopen or bsddb.rnopen) and passed to the constructor. See the module's __doc__ string for an overview of the interface. u utf-8c C s t j | | | | | � d S( N( u Shelfu __init__( u selfu dictu protocolu writebacku keyencoding( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __init__� s u BsdDbShelf.__init__c C sF | j j | � \ } } t | � } | j | j � t | � j � f S( N( u dictu set_locationu BytesIOu decodeu keyencodingu Unpickleru load( u selfu keyu valueu f( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu set_location� s u BsdDbShelf.set_locationc C sC t | j � \ } } t | � } | j | j � t | � j � f S( N( u nextu dictu BytesIOu decodeu keyencodingu Unpickleru load( u selfu keyu valueu f( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu next� s u BsdDbShelf.nextc C sC | j j � \ } } t | � } | j | j � t | � j � f S( N( u dictu previousu BytesIOu decodeu keyencodingu Unpickleru load( u selfu keyu valueu f( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu previous� s u BsdDbShelf.previousc C sC | j j � \ } } t | � } | j | j � t | � j � f S( N( u dictu firstu BytesIOu decodeu keyencodingu Unpickleru load( u selfu keyu valueu f( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu first� s u BsdDbShelf.firstc C sC | j j � \ } } t | � } | j | j � t | � j � f S( N( u dictu lastu BytesIOu decodeu keyencodingu Unpickleru load( u selfu keyu valueu f( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu last� s u BsdDbShelf.lastNF( u __name__u __module__u __qualname__u __doc__u Noneu Falseu __init__u set_locationu nextu previousu firstu last( u __locals__( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu BsdDbShelf� s c B s/ | Ee Z d Z d Z d d d d d � Z d S( u DbfilenameShelfu� Shelf implementation using the "dbm" generic dbm interface. This is initialized with the filename for the dbm database. See the module's __doc__ string for an overview of the interface. u cc C s2 d d l } t j | | j | | � | | � d S( Ni ( u dbmu Shelfu __init__u open( u selfu filenameu flagu protocolu writebacku dbm( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu __init__� s u DbfilenameShelf.__init__NF( u __name__u __module__u __qualname__u __doc__u Noneu Falseu __init__( u __locals__( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu DbfilenameShelf� s u cc C s t | | | | � S( u Open a persistent dictionary for reading and writing. The filename parameter is the base filename for the underlying database. As a side-effect, an extension may be added to the filename and more than one file may be created. The optional flag parameter has the same interpretation as the flag parameter of dbm.open(). The optional protocol parameter specifies the version of the pickle protocol (0, 1, or 2). See the module's __doc__ string for an overview of the interface. ( u DbfilenameShelf( u filenameu flagu protocolu writeback( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu open� s F( u __doc__u pickleu Pickleru Unpickleru iou BytesIOu collectionsu __all__u MutableMappingu _ClosedDictu Shelfu BsdDbShelfu DbfilenameShelfu Noneu Falseu open( ( ( u+ /opt/alt/python33/lib64/python3.3/shelve.pyu <module>9 s W+
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