# A wrapper around the (optional) built-in class dbm, supporting keys
# and values of almost any type instead of just string.
# (Actually, this works only for keys and values that can be read back
# correctly after being converted to a string.)
class Dbm:
def __init__(self, filename, mode, perm):
import dbm.ndbm
self.db = dbm.ndbm.open(filename, mode, perm)
def __repr__(self):
s = ''
for key in self.keys():
t = repr(key) + ': ' + repr(self[key])
if s: t = ', ' + t
s = s + t
return '{' + s + '}'
def __len__(self):
return len(self.db)
def __getitem__(self, key):
return eval(self.db[repr(key)])
def __setitem__(self, key, value):
self.db[repr(key)] = repr(value)
def __delitem__(self, key):
del self.db[repr(key)]
def keys(self):
res = []
for key in self.db.keys():
res.append(eval(key))
return res
def has_key(self, key):
return repr(key) in self.db
def test():
d = Dbm('@dbm', 'rw', 0o600)
print(d)
while 1:
try:
key = eval(input('key: '))
if key in d:
value = d[key]
print('currently:', value)
value = eval(input('value: '))
if value is None:
del d[key]
else:
d[key] = value
except KeyboardInterrupt:
print('')
print(d)
except EOFError:
print('[eof]')
break
print(d)
test()
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