author | Todd Larsen <tlarsen@google.com> |
Mon, 10 Nov 2008 18:00:47 +0000 | |
changeset 467 | 07441582717a |
parent 275 | 78fd8c2ed80a |
permissions | -rw-r--r-- |
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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#!/usr/bin/python2.5 |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# Copyright 2008 the Melange authors. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# Licensed under the Apache License, Version 2.0 (the "License"); |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# you may not use this file except in compliance with the License. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# You may obtain a copy of the License at |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
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# http://www.apache.org/licenses/LICENSE-2.0 |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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# |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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# Unless required by applicable law or agreed to in writing, software |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# distributed under the License is distributed on an "AS IS" BASIS, |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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# See the License for the specific language governing permissions and |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# limitations under the License. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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"""Like Django SortedDict, but no repeated assignments to the same key. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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""" |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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__authors__ = [ |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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'"Todd Larsen" <tlarsen@google.com>', |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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] |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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from django.utils import datastructures |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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class NoOverwriteSortedDict(datastructures.SortedDict): |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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"""SortedDict where each key can be given a value only once. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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The purpose of this data structure is to be able to detect when |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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an attempt is made to overwrite the value of an existing key |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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in the SortedDict. This is to catch, for example, cases such as |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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a registry where two different callers attempt to register the |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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same view, handler, etc. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
changeset
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It is still possible to pop or del a key out of the dict and then |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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add it back to the dict. |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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""" |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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KEY_ALREADY_PRESENT_ERROR_FMT = \ |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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'%s already present, value cannot be overwritten' |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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def __init__(self, data=None): |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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if data is None: |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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data = {} |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# call SortedDict's parent __init__() |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# (bypassing the __init__() of SortedDict itself, since it will not |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
diff
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# enforce our no-overwrite requirement) |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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super(datastructures.SortedDict, self).__init__(data) |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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if isinstance(data, dict): |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
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parents:
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self.keyOrder = data.keys() |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
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parents:
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else: |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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self.keyOrder = [] |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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for key, value in data: |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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if key in self.keyOrder: |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# key has already been given a value, and that value is not |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# permitted to be overwritten, so raise an error |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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raise KeyError(self.KEY_ALREADY_PRESENT_ERROR_FMT % key) |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
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parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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self.keyOrder.append(key) |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
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parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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def __setitem__(self, key, value): |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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if key in self.keyOrder: |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# key has already been given a value, and that value is not permitted |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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# to be overwritten, so raise an error |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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raise KeyError(self.KEY_ALREADY_PRESENT_ERROR_FMT % key) |
78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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78fd8c2ed80a
A specialized SortedDict used by soc/logic/site/page.py.
Todd Larsen <tlarsen@google.com>
parents:
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super(NoOverwriteSortedDict, self).__setitem__(key, value) |