+
−#!/usr/bin/python2.5
+
−#
+
−# Copyright 2008 the Melange authors.
+
−#
+
−# Licensed under the Apache License, Version 2.0 (the "License");
+
−# you may not use this file except in compliance with the License.
+
−# You may obtain a copy of the License at
+
−#
+
−#   http://www.apache.org/licenses/LICENSE-2.0
+
−#
+
−# Unless required by applicable law or agreed to in writing, software
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−# distributed under the License is distributed on an "AS IS" BASIS,
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−# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+
−# See the License for the specific language governing permissions and
+
−# limitations under the License.
+
−
+
−"""Logic related to handling dictionaries
+
−"""
+
−
+
−__authors__ = [
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−  '"Sverre Rabbelier" <sverre@rabbelier.nl>',
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−  ]
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−
+
−
+
−def merge(target, updates):
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−  """Like the builtin 'update' method but does not overwrite existing values
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−
+
−  Args:
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−    target: The dictionary that is to be updated, may be None
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−    updates: A dictionary containing new values for the original dict
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−
+
−  Returns:
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−    the target dict, with any missing values from updates merged in, in-place 
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−  """
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−
+
−  if not target:
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−    target = {}
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−
+
−  for key, value in updates.iteritems():
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−    if key not in target:
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−      target[key] = value
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−
+
−  return target