############################################################################## # # Copyright (c) 2001, 2002 Zope Corporation and Contributors. # All Rights Reserved. # # This software is subject to the provisions of the Zope Public License, # Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution. # THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED # WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED # WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS # FOR A PARTICULAR PURPOSE. # ############################################################################## """Ordered container implementation. $Id: ordered.py 40368 2005-11-25 15:09:45Z efge $ """ __docformat__ = 'restructuredtext' from zope.app.container.interfaces import IOrderedContainer from zope.interface import implements from persistent import Persistent from persistent.dict import PersistentDict from persistent.list import PersistentList from types import StringTypes, TupleType, ListType from zope.app.container.contained import Contained, setitem, uncontained from zope.app.container.contained import notifyContainerModified class OrderedContainer(Persistent, Contained): """ `OrderedContainer` maintains entries' order as added and moved. >>> oc = OrderedContainer() >>> int(IOrderedContainer.providedBy(oc)) 1 >>> len(oc) 0 """ implements(IOrderedContainer) def __init__(self): self._data = PersistentDict() self._order = PersistentList() def keys(self): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc.keys() [] >>> oc['foo'] = 'bar' >>> oc.keys() ['foo'] >>> oc['baz'] = 'quux' >>> oc.keys() ['foo', 'baz'] >>> int(len(oc._order) == len(oc._data)) 1 """ return self._order[:] def __iter__(self): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc.keys() [] >>> oc['foo'] = 'bar' >>> oc['baz'] = 'quux' >>> [i for i in oc] ['foo', 'baz'] >>> int(len(oc._order) == len(oc._data)) 1 """ return iter(self.keys()) def __getitem__(self, key): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc['foo'] = 'bar' >>> oc['foo'] 'bar' """ return self._data[key] def get(self, key, default=None): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc['foo'] = 'bar' >>> oc.get('foo') 'bar' >>> oc.get('funky', 'No chance, dude.') 'No chance, dude.' """ return self._data.get(key, default) def values(self): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc.keys() [] >>> oc['foo'] = 'bar' >>> oc.values() ['bar'] >>> oc['baz'] = 'quux' >>> oc.values() ['bar', 'quux'] >>> int(len(oc._order) == len(oc._data)) 1 """ return [self._data[i] for i in self._order] def __len__(self): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> int(len(oc) == 0) 1 >>> oc['foo'] = 'bar' >>> int(len(oc) == 1) 1 """ return len(self._data) def items(self): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc.keys() [] >>> oc['foo'] = 'bar' >>> oc.items() [('foo', 'bar')] >>> oc['baz'] = 'quux' >>> oc.items() [('foo', 'bar'), ('baz', 'quux')] >>> int(len(oc._order) == len(oc._data)) 1 """ return [(i, self._data[i]) for i in self._order] def __contains__(self, key): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc['foo'] = 'bar' >>> int('foo' in oc) 1 >>> int('quux' in oc) 0 """ return self._data.has_key(key) has_key = __contains__ def __setitem__(self, key, object): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc.keys() [] >>> oc['foo'] = 'bar' >>> oc._order ['foo'] >>> oc['baz'] = 'quux' >>> oc._order ['foo', 'baz'] >>> int(len(oc._order) == len(oc._data)) 1 """ existed = self._data.has_key(key) bad = False if isinstance(key, StringTypes): try: unicode(key) except UnicodeError: bad = True else: bad = True if bad: raise TypeError("'%s' is invalid, the key must be an " "ascii or unicode string" % key) if len(key) == 0: raise ValueError("The key cannot be an empty string") setitem(self, self._data.__setitem__, key, object) if not existed: self._order.append(key) return key def __delitem__(self, key): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc.keys() [] >>> oc['foo'] = 'bar' >>> oc['baz'] = 'quux' >>> oc['zork'] = 'grue' >>> oc.items() [('foo', 'bar'), ('baz', 'quux'), ('zork', 'grue')] >>> int(len(oc._order) == len(oc._data)) 1 >>> del oc['baz'] >>> oc.items() [('foo', 'bar'), ('zork', 'grue')] >>> int(len(oc._order) == len(oc._data)) 1 """ uncontained(self._data[key], self, key) del self._data[key] self._order.remove(key) def updateOrder(self, order): """ See `IOrderedContainer`. >>> oc = OrderedContainer() >>> oc['foo'] = 'bar' >>> oc['baz'] = 'quux' >>> oc['zork'] = 'grue' >>> oc.keys() ['foo', 'baz', 'zork'] >>> oc.updateOrder(['baz', 'foo', 'zork']) >>> oc.keys() ['baz', 'foo', 'zork'] >>> oc.updateOrder(['baz', 'zork', 'foo']) >>> oc.keys() ['baz', 'zork', 'foo'] >>> oc.updateOrder(['baz', 'zork', 'foo']) >>> oc.keys() ['baz', 'zork', 'foo'] >>> oc.updateOrder(('zork', 'foo', 'baz')) >>> oc.keys() ['zork', 'foo', 'baz'] >>> oc.updateOrder(['baz', 'zork']) Traceback (most recent call last): ... ValueError: Incompatible key set. >>> oc.updateOrder(['foo', 'bar', 'baz', 'quux']) Traceback (most recent call last): ... ValueError: Incompatible key set. >>> oc.updateOrder(1) Traceback (most recent call last): ... TypeError: order must be a tuple or a list. >>> oc.updateOrder('bar') Traceback (most recent call last): ... TypeError: order must be a tuple or a list. >>> oc.updateOrder(['baz', 'zork', 'quux']) Traceback (most recent call last): ... ValueError: Incompatible key set. >>> del oc['baz'] >>> del oc['zork'] >>> del oc['foo'] >>> len(oc) 0 """ if not isinstance(order, ListType) and \ not isinstance(order, TupleType): raise TypeError('order must be a tuple or a list.') if len(order) != len(self._order): raise ValueError("Incompatible key set.") was_dict = {} will_be_dict = {} new_order = PersistentList() for i in range(len(order)): was_dict[self._order[i]] = 1 will_be_dict[order[i]] = 1 new_order.append(order[i]) if will_be_dict != was_dict: raise ValueError("Incompatible key set.") self._order = new_order notifyContainerModified(self)