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diff --git a/roundup/cgi/ZTUtils/Batch.py b/roundup/cgi/ZTUtils/Batch.py
--- /dev/null
@@ -0,0 +1,119 @@
+##############################################################################
+#
+# Copyright (c) 2001 Zope Corporation and Contributors. All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.0 (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
+#
+##############################################################################
+__doc__='''Batch class, for iterating over a sequence in batches
+
+$Id: Batch.py,v 1.1 2002-09-05 00:37:09 richard Exp $'''
+__version__='$Revision: 1.1 $'[11:-2]
+
+class LazyPrevBatch:
+ def __of__(self, parent):
+ return Batch(parent._sequence, parent._size,
+ parent.first - parent._size + parent.overlap, 0,
+ parent.orphan, parent.overlap)
+
+class LazyNextBatch:
+ def __of__(self, parent):
+ try: parent._sequence[parent.end]
+ except IndexError: return None
+ return Batch(parent._sequence, parent._size,
+ parent.end - parent.overlap, 0,
+ parent.orphan, parent.overlap)
+
+class LazySequenceLength:
+ def __of__(self, parent):
+ parent.sequence_length = l = len(parent._sequence)
+ return l
+
+class Batch:
+ """Create a sequence batch"""
+ __allow_access_to_unprotected_subobjects__ = 1
+
+ previous = LazyPrevBatch()
+ next = LazyNextBatch()
+ sequence_length = LazySequenceLength()
+
+ def __init__(self, sequence, size, start=0, end=0,
+ orphan=0, overlap=0):
+ '''Encapsulate "sequence" in batches of "size".
+
+ Arguments: "start" and "end" are 0-based indexes into the
+ sequence. If the next batch would contain no more than
+ "orphan" elements, it is combined with the current batch.
+ "overlap" is the number of elements shared by adjacent
+ batches. If "size" is not specified, it is computed from
+ "start" and "end". Failing that, it is 7.
+
+ Attributes: Note that the "start" attribute, unlike the
+ argument, is a 1-based index (I know, lame). "first" is the
+ 0-based index. "length" is the actual number of elements in
+ the batch.
+
+ "sequence_length" is the length of the original, unbatched, sequence
+ '''
+
+ start = start + 1
+
+ start,end,sz = opt(start,end,size,orphan,sequence)
+
+ self._sequence = sequence
+ self.size = sz
+ self._size = size
+ self.start = start
+ self.end = end
+ self.orphan = orphan
+ self.overlap = overlap
+ self.first = max(start - 1, 0)
+ self.length = self.end - self.first
+ if self.first == 0:
+ self.previous = None
+
+
+ def __getitem__(self, index):
+ if index < 0:
+ if index + self.end < self.first: raise IndexError, index
+ return self._sequence[index + self.end]
+
+ if index >= self.length: raise IndexError, index
+ return self._sequence[index+self.first]
+
+ def __len__(self):
+ return self.length
+
+def opt(start,end,size,orphan,sequence):
+ if size < 1:
+ if start > 0 and end > 0 and end >= start:
+ size=end+1-start
+ else: size=7
+
+ if start > 0:
+
+ try: sequence[start-1]
+ except IndexError: start=len(sequence)
+
+ if end > 0:
+ if end < start: end=start
+ else:
+ end=start+size-1
+ try: sequence[end+orphan-1]
+ except IndexError: end=len(sequence)
+ elif end > 0:
+ try: sequence[end-1]
+ except IndexError: end=len(sequence)
+ start=end+1-size
+ if start - 1 < orphan: start=1
+ else:
+ start=1
+ end=start+size-1
+ try: sequence[end+orphan-1]
+ except IndexError: end=len(sequence)
+ return start,end,size