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#
# This file is part of the LibreOffice project.
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# This file incorporates work covered by the following license notice:
#
# 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 .
#
import sys
import globals
def toString (node):
if node == None:
return ''
chars = '('
if type(node.left) == type(0):
chars += "%d"%node.left
else:
chars += toString(node.left)
chars += node.op
if type(node.right) == type(0):
chars += "%d"%node.right
else:
chars += toString(node.right)
chars += ")"
return chars
class Node(object):
def __init__ (self):
self.left = None
self.right = None
self.parent = None
self.op = None
class ExpParser(object):
def __init__ (self, tokens):
self.tokens = tokens
def jumpToRoot (self):
while self.ptr.parent != None:
self.ptr = self.ptr.parent
def build (self):
self.ptr = Node()
for token in self.tokens:
if token in '+-':
if self.ptr.left == None:
raise globals.ParseError ('')
if self.ptr.right == None:
self.ptr.op = token
else:
self.jumpToRoot()
self.ptr.parent = Node()
self.ptr.parent.left = self.ptr
self.ptr = self.ptr.parent
self.ptr.op = token
elif token in '*/':
if self.ptr.left == None:
raise globals.ParseError ('')
elif self.ptr.right == None:
self.ptr.op = token
else:
num = self.ptr.right
self.ptr.right = Node()
self.ptr.right.parent = self.ptr
self.ptr.right.left = num
self.ptr.right.op = token
self.ptr = self.ptr.right
elif token == '(':
if self.ptr.left == None:
self.ptr.left = Node()
self.ptr.left.parent = self.ptr
self.ptr = self.ptr.left
elif self.ptr.right == None:
self.ptr.right = Node()
self.ptr.right.parent = self.ptr
self.ptr = self.ptr.right
else:
raise globals.ParseError ('')
elif token == ')':
if self.ptr.left == None:
raise globals.ParseError ('')
elif self.ptr.right == None:
raise globals.ParseError ('')
elif self.ptr.parent == None:
pass
else:
self.ptr = self.ptr.parent
else:
num = int(token)
if self.ptr.left == None:
self.ptr.left = num
elif self.ptr.right == None:
self.ptr.right = num
else:
raise globals.ParseError ('')
def dumpTree (self):
self.jumpToRoot()
print toString(self.ptr)
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