diff options
Diffstat (limited to 'Lib/shelve.py')
| -rw-r--r-- | Lib/shelve.py | 50 |
1 files changed, 30 insertions, 20 deletions
diff --git a/Lib/shelve.py b/Lib/shelve.py index 8f709a2..b159e61 100644 --- a/Lib/shelve.py +++ b/Lib/shelve.py @@ -28,8 +28,17 @@ Dependent on the implementation, closing a persistent dictionary may or may not be necessary to flush changes to disk. """ -import pickle -import StringIO +# Try using cPickle and cStringIO if available. + +try: + from cPickle import Pickler, Unpickler +except ImportError: + from pickle import Pickler, Unpickler + +try: + from cStringIO import StringIO +except ImportError: + from StringIO import StringIO class Shelf: @@ -52,12 +61,12 @@ class Shelf: return self.dict.has_key(key) def __getitem__(self, key): - f = StringIO.StringIO(self.dict[key]) - return pickle.Unpickler(f).load() + f = StringIO(self.dict[key]) + return Unpickler(f).load() def __setitem__(self, key, value): - f = StringIO.StringIO() - p = pickle.Pickler(f) + f = StringIO() + p = Pickler(f) p.dump(value) self.dict[key] = f.getvalue() @@ -80,11 +89,12 @@ class Shelf: class BsdDbShelf(Shelf): """Shelf implementation using the "BSD" db interface. - The actual database is opened using one of thethe "bsddb" modules - "open" routines (i.e. bsddb.hashopen, bsddb.btopen or bsddb.rnopen.) + This adds methods first(), next(), previous(), last() and + set_location() that have no counterpart in [g]dbm databases. - This class is initialized with the the database object - returned from one of the bsddb open functions. + 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. """ @@ -94,28 +104,28 @@ class BsdDbShelf(Shelf): def set_location(self, key): (key, value) = self.dict.set_location(key) - f = StringIO.StringIO(value) - return (key, pickle.Unpickler(f).load()) + f = StringIO(value) + return (key, Unpickler(f).load()) def next(self): (key, value) = self.dict.next() - f = StringIO.StringIO(value) - return (key, pickle.Unpickler(f).load()) + f = StringIO(value) + return (key, Unpickler(f).load()) def previous(self): (key, value) = self.dict.previous() - f = StringIO.StringIO(value) - return (key, pickle.Unpickler(f).load()) + f = StringIO(value) + return (key, Unpickler(f).load()) def first(self): (key, value) = self.dict.first() - f = StringIO.StringIO(value) - return (key, pickle.Unpickler(f).load()) + f = StringIO(value) + return (key, Unpickler(f).load()) def last(self): (key, value) = self.dict.last() - f = StringIO.StringIO(value) - return (key, pickle.Unpickler(f).load()) + f = StringIO(value) + return (key, Unpickler(f).load()) class DbfilenameShelf(Shelf): |