def createTreeHelper():
nextToken = stack.pop()
newNode = None
if nextToken == "(":
newNode = createTreeHelper()
elif scanner.isConstant(nextToken):
newNode = Node(nextToken)
elif scanner.isOperator(nextToken):
newNode = Node(nextToken)
leftOperand = stack.pop()
if leftOperand == "(":
newNode.leftChild = createTreeHelper()
elif scanner.isConstant(leftOperand):
newNode.leftChild = Node(leftOperand)
else:
raise CreateParseTreeException(stack)
if scanner.getArgCount(nextToken) == 2:
rightOperand = stack.pop()
if rightOperand == "(":
newNode.rightChild = createTreeHelper()
elif scanner.isConstant(rightOperand):
newNode.rightChild = Node(rightOperand)
else:
raise CreateParseTreeException(stack)
else:
raise CreateParseTreeException(stack)
lastToken = stack.pop()
if lastToken != ")":
raise CreateParseTreeException(stack)
return newNode
def printTreeTraversalHelper(currentNode):
if currentNode is None:
return None
leftType = printTreeTraversalHelper(currentNode.leftChild)
rightType = printTreeTraversalHelper(currentNode.rightChild)
if scanner.isConstant(currentNode.data):
if scanner.isReal(currentNode.data):
print currentNode.data + "e "
elif scanner.isString(currentNode.data):
print "s\" " + currentNode.data[1:]
else:
print currentNode.data
return (scanner.getToken(currentNode.data)).Type
elif scanner.isOperator(currentNode.data):
numberOperands = scanner.getArgCount(currentNode.data)
if numberOperands == 1 and rightType is None:
# if operand is Real add a f in front of the operator
if leftType == "Real" and rightType is None:
print "f" + currentNode.data
#if there is an integer using a real operation then convert the integer to real
if leftType == "Integer" and scanner.isRealOperator(currentNode.data):
print currentNode.data
print "s>f"
#is boolean type child and operator is boolean
if leftType == "Boolean" and scanner.isBooleanOperator(currentNode.data):
print itblToGforth(currentNode.data)
#is integer type child and is integer operator
if leftType == "Integer" and not scanner.isBooleanOperator(currentNode.data):
print currentNode.data
else:
raise ParseTreeException(currentNode)
return leftType
elif numberOperands == 2:
#children are same value no conversion needed
if leftType == rightType:
# children are real and real operator
if leftType == "Real" and scanner.isRealOperator(currentNode.data):
print "f" + itblToGforth(currentNode.data) + " "
# children are string and a +
elif leftType == "String":
if currentNode.data == "+":
print "s" + itblToGforth(currentNode.data) + " "
else:
raise ParseTreeException(currentNode)
# children are boolean and boolean operator
elif leftType == "Boolean" and scanner.isBooleanOperator(currentNode.data):
print itblToGforth(currentNode.data)
# children are integers and integer operator
elif leftType == "Integer" and not scanner.isBooleanOperator(currentNode.data):
if currentNode.data == "^":
print "s>f"
print "s>f"
print "f" + itblToGforth(currentNode.data)
leftType = "Real"
else:
print itblToGforth(currentNode.data)
# bad parse
else:
raise ParseTreeException(currentNode)
return leftType
# type conversion needed to float
elif (((leftType == "Integer" and rightType == "Real") or (leftType == "Real" and rightType == "Integer")) and not scanner.isBooleanOperator(currentNode.data)):
print "s>f"
if leftType == "Integer":
print "fswap"
print "f" + itblToGforth(currentNode.data)
return "Real"
else:
raise ParseTreeException(currentNode)
else:
return None