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diff --git a/sca-java-2.x/tags/2.0.1-RC1/modules/implementation-python-runtime/src/main/resources/util.py b/sca-java-2.x/tags/2.0.1-RC1/modules/implementation-python-runtime/src/main/resources/util.py
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+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you 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 distributed under the License is distributed on an
+# "AS IS" BASIS, 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.
+
+# Simple utility functions
+from sys import maxint
+
+# Scheme-like lists
+def cons(a, b):
+ return (a,) + b
+
+def car(l):
+ return l[0]
+
+def first(l):
+ return car(l)
+
+def cdr(l):
+ return l[1:]
+
+def rest(l):
+ return cdr(l)
+
+def cadr(l):
+ return car(cdr(l))
+
+def cddr(l):
+ return cdr(cdr(l))
+
+def caddr(l):
+ return car(cddr(l))
+
+def append(a, b):
+ return a + b
+
+def reverse(l):
+ r = list(l)
+ r.reverse()
+ return tuple(r)
+
+def isNil(l):
+ if isinstance(l, streampair):
+ return l.isNil()
+ return l == ()
+
+def isSymbol(v):
+ return isinstance(v, basestring) and v[0:1] == "'"
+
+def isList(v):
+ if getattr(v, '__iter__', False) == False:
+ return False
+ if isinstance(v, basestring) or isinstance(v, dict):
+ return False
+ return True
+
+def isTaggedList(v, t):
+ return isList(v) and not isNil(v) and car(v) == t
+
+
+# Scheme-like streams
+class streampair(object):
+ def __init__(self, car, cdr):
+ self.car = car
+ self.cdr = cdr
+
+ def __repr__(self):
+ return repr(self[0:len(self)])
+
+ def isNil(self):
+ return self.cdr == ()
+
+ def __len__(self):
+ if self.cdr == ():
+ return 0
+ return 1 + len(self.cdr())
+
+ def __getitem__(self, i):
+ if i == 0:
+ return self.car
+ return self.cdr()[i - 1]
+
+ def __getslice__(self, i, j):
+ if isNil(self):
+ return ()
+ if i > 0:
+ if j == maxint:
+ return self.cdr()[i - 1: j]
+ return self.cdr()[i - 1: j - 1]
+ if j == maxint:
+ return self
+ if j == 0:
+ return (self.car,)
+ return (self.car,) + self.cdr()[: j - 1]
+
+ def __eq__(self, other):
+ sl = len(self)
+ ol = len(other)
+ if sl != ol:
+ return False
+ return self[0: sl] == other[0: ol]
+
+ def __ne__(self, other):
+ return not self.__eq__(other)
+
+def cons_stream(car, cdr):
+ return streampair(car, cdr)
+
+
+# Scheme-like associations
+def assoc(k, l):
+ if l == ():
+ return None
+
+ if k == car(car(l)):
+ return car(l)
+ return assoc(k, cdr(l))
+
+# Currying / partial function application
+def curry(f, *args):
+ return lambda *a: f(*(args + a))
+
+# Split a path into a list of segments
+def tokens(path):
+ return tuple(filter(lambda s: len(s) != 0, path.split("/")))
+
+# Write a list of strings to a stream
+def writeStrings(l, os):
+ if l == ():
+ return os
+ os.write(car(l))
+ return writeStrings(cdr(l), os)
+