"""ulist is a subclass of list where items cannot appear twice in the list.
[1,2,2,3,3,4] is a valid list, whereas in ulist we can only have [1,2,3,4].
__author__ = "gemalto http://www.gemalto.com"
Copyright 2001-2010 gemalto
Author: Jean-Daniel Aussel, mailto:jean-daniel.aussel@gemalto.com
This file is part of pyscard.
pyscard is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
pyscard is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with pyscard; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
"""
class ulist(list):
"""ulist ensures that all items are unique and provides an __onadditem__
hook to perform custom action in subclasses."""
#
# override list methods
#
def __init__(self, initlist=None):
if initlist is not None and initlist!=[]:
list.__init__( self, [initlist[0]] )
for item in initlist[1:]:
if not list.__contains__( self, item ):
list.append( self, item )
else:
list.__init__( self, initlist )
def __add__(self, other):
newother = self.__remove_duplicates( other )
self.__appendother__( newother )
return self.__class__( list(self)+list(newother) )
def __iadd__(self, other):
newother = self.__remove_duplicates( other )
self.__appendother__( newother )
list.__iadd__( self, newother )
return self
def __radd__(self, other):
newother = self.__remove_duplicates( other )
return list.__add__( self, newother )
def append(self, item):
if not list.__contains__( self, item ):
list.append( self, item )
self.__onadditem__( item )
def insert(self, i, item):
if not list.__contains__( self, item ):
list.insert( self, i, item )
self.__onadditem__( item )
def pop(self, i=-1):
item = list.pop( self, i )
self.__onremoveitem__( item )
return item
def remove(self, item):
list.remove( self, item )
self.__onremoveitem__( item )
#
# non list methods
#
def __remove_duplicates( self, _other ):
"""Remove from other items already in list."""
if not isinstance( _other, type(self) ) \
and not isinstance( _other, type(list)) \
and not isinstance( _other, type([])):
other=[_other]
else:
other=list(_other)
# remove items already in self
newother=[]
for i in range(0, len(other) ):
item = other.pop(0)
if not list.__contains__( self, item ):
newother.append( item )
# remove duplicate items in other
other=[]
if newother!=[]:
other.append(newother[0])
for i in range( 1, len( newother ) ):
item = newother.pop()
if not other.__contains__( item ):
other.append( item )
return other
def __appendother__( self, other ):
"""Append other to object."""
for item in other:
self.__onadditem__( item )
def __onadditem__( self, item ):
"""Called for each item added. Override in subclasses for adding custom action."""
pass
def __onremoveitem__( self, item ):
"""Called for each item removed. Override in subclasses for adding custom action."""
pass
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