1 files changed, 111 insertions, 0 deletions
diff --git a/toolkit/src2xml/source/expression.py b/toolkit/src2xml/source/expression.py
new file mode 100644
index 000000000000..b5f58c42d112
--- /dev/null
+++ b/toolkit/src2xml/source/expression.py
@@ -0,0 +1,111 @@
+
+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)
+
+
+
+