App Engine Python SDK  v1.6.9 rev.445
The Python runtime is available as an experimental Preview feature.
Public Member Functions | List of all members
google.appengine._internal.antlr3.tree.TreeAdaptor Class Reference
Inheritance diagram for google.appengine._internal.antlr3.tree.TreeAdaptor:
google.appengine._internal.antlr3.tree.BaseTreeAdaptor google.appengine._internal.antlr3.tree.CommonTreeAdaptor google.appengine._internal.antlr3.treewizard.TreePatternTreeAdaptor

Public Member Functions

def createWithPayload
 
def dupNode
 
def dupTree
 
def nil
 
def errorNode
 
def isNil
 
def addChild
 
def becomeRoot
 
def rulePostProcessing
 
def getUniqueID
 
def createFromToken
 
def createFromType
 
def getType
 
def setType
 
def getText
 
def setText
 
def getToken
 
def setTokenBoundaries
 
def getTokenStartIndex
 
def getTokenStopIndex
 
def getChild
 
def setChild
 
def deleteChild
 
def getChildCount
 
def getParent
 
def setParent
 
def getChildIndex
 
def setChildIndex
 
def replaceChildren
 
def create
 

Detailed Description

@brief Abstract baseclass for tree adaptors.

How to create and navigate trees.  Rather than have a separate factory
and adaptor, I've merged them.  Makes sense to encapsulate.

This takes the place of the tree construction code generated in the
generated code in 2.x and the ASTFactory.

I do not need to know the type of a tree at all so they are all
generic Objects.  This may increase the amount of typecasting needed. :(

Member Function Documentation

def google.appengine._internal.antlr3.tree.TreeAdaptor.addChild (   self,
  t,
  child 
)
Add a child to the tree t.  If child is a flat tree (a list), make all
in list children of t.  Warning: if t has no children, but child does
and child isNil then you can decide it is ok to move children to t via
t.children = child.children; i.e., without copying the array.  Just
make sure that this is consistent with have the user will build
ASTs. Do nothing if t or child is null.
def google.appengine._internal.antlr3.tree.TreeAdaptor.becomeRoot (   self,
  newRoot,
  oldRoot 
)
If oldRoot is a nil root, just copy or move the children to newRoot.
If not a nil root, make oldRoot a child of newRoot.

   old=^(nil a b c), new=r yields ^(r a b c)
   old=^(a b c), new=r yields ^(r ^(a b c))

If newRoot is a nil-rooted single child tree, use the single
child as the new root node.

   old=^(nil a b c), new=^(nil r) yields ^(r a b c)
   old=^(a b c), new=^(nil r) yields ^(r ^(a b c))

If oldRoot was null, it's ok, just return newRoot (even if isNil).

   old=null, new=r yields r
   old=null, new=^(nil r) yields ^(nil r)

Return newRoot.  Throw an exception if newRoot is not a
simple node or nil root with a single child node--it must be a root
node.  If newRoot is ^(nil x) return x as newRoot.

Be advised that it's ok for newRoot to point at oldRoot's
children; i.e., you don't have to copy the list.  We are
constructing these nodes so we should have this control for
efficiency.
def google.appengine._internal.antlr3.tree.TreeAdaptor.create (   self,
  args 
)
Deprecated, use createWithPayload, createFromToken or createFromType.

This method only exists to mimic the Java interface of TreeAdaptor.
def google.appengine._internal.antlr3.tree.TreeAdaptor.createFromToken (   self,
  tokenType,
  fromToken,
  text = None 
)
Create a new node derived from a token, with a new token type and
(optionally) new text.

This is invoked from an imaginary node ref on right side of a
rewrite rule as IMAG[$tokenLabel] or IMAG[$tokenLabel "IMAG"].

This should invoke createToken(Token).
def google.appengine._internal.antlr3.tree.TreeAdaptor.createFromType (   self,
  tokenType,
  text 
)
Create a new node derived from a token, with a new token type.

This is invoked from an imaginary node ref on right side of a
rewrite rule as IMAG["IMAG"].

This should invoke createToken(int,String).
def google.appengine._internal.antlr3.tree.TreeAdaptor.createWithPayload (   self,
  payload 
)
Create a tree node from Token object; for CommonTree type trees,
then the token just becomes the payload.  This is the most
common create call.

Override if you want another kind of node to be built.
def google.appengine._internal.antlr3.tree.TreeAdaptor.deleteChild (   self,
  t,
  i 
)
Remove ith child and shift children down from right.
def google.appengine._internal.antlr3.tree.TreeAdaptor.dupNode (   self,
  treeNode 
)
Duplicate a single tree node.

Override if you want another kind of node to be built.
def google.appengine._internal.antlr3.tree.TreeAdaptor.dupTree (   self,
  tree 
)
Duplicate tree recursively, using dupNode() for each node
def google.appengine._internal.antlr3.tree.TreeAdaptor.errorNode (   self,
  input,
  start,
  stop,
  exc 
)
Return a tree node representing an error.  This node records the
tokens consumed during error recovery.  The start token indicates the
input symbol at which the error was detected.  The stop token indicates
the last symbol consumed during recovery.

You must specify the input stream so that the erroneous text can
be packaged up in the error node.  The exception could be useful
to some applications; default implementation stores ptr to it in
the CommonErrorNode.

This only makes sense during token parsing, not tree parsing.
Tree parsing should happen only when parsing and tree construction
succeed.
def google.appengine._internal.antlr3.tree.TreeAdaptor.getChild (   self,
  t,
  i 
)
Get a child 0..n-1 node
def google.appengine._internal.antlr3.tree.TreeAdaptor.getChildCount (   self,
  t 
)
How many children?  If 0, then this is a leaf node
def google.appengine._internal.antlr3.tree.TreeAdaptor.getChildIndex (   self,
  t 
)
What index is this node in the child list? Range: 0..n-1
If your node type doesn't handle this, it's ok but the tree rewrites
in tree parsers need this functionality.
def google.appengine._internal.antlr3.tree.TreeAdaptor.getParent (   self,
  t 
)
Who is the parent node of this node; if null, implies node is root.
If your node type doesn't handle this, it's ok but the tree rewrites
in tree parsers need this functionality.
def google.appengine._internal.antlr3.tree.TreeAdaptor.getToken (   self,
  t 
)
Return the token object from which this node was created.

Currently used only for printing an error message.
The error display routine in BaseRecognizer needs to
display where the input the error occurred. If your
tree of limitation does not store information that can
lead you to the token, you can create a token filled with
the appropriate information and pass that back.  See
BaseRecognizer.getErrorMessage().
def google.appengine._internal.antlr3.tree.TreeAdaptor.getTokenStartIndex (   self,
  t 
)
Get the token start index for this subtree; return -1 if no such index
def google.appengine._internal.antlr3.tree.TreeAdaptor.getTokenStopIndex (   self,
  t 
)
Get the token stop index for this subtree; return -1 if no such index
def google.appengine._internal.antlr3.tree.TreeAdaptor.getType (   self,
  t 
)
For tree parsing, I need to know the token type of a node
def google.appengine._internal.antlr3.tree.TreeAdaptor.getUniqueID (   self,
  node 
)
For identifying trees.

How to identify nodes so we can say "add node to a prior node"?
Even becomeRoot is an issue.  Use System.identityHashCode(node)
usually.
def google.appengine._internal.antlr3.tree.TreeAdaptor.isNil (   self,
  tree 
)
Is tree considered a nil node used to make lists of child nodes?
def google.appengine._internal.antlr3.tree.TreeAdaptor.nil (   self)
Return a nil node (an empty but non-null node) that can hold
a list of element as the children.  If you want a flat tree (a list)
use "t=adaptor.nil(); t.addChild(x); t.addChild(y);"
def google.appengine._internal.antlr3.tree.TreeAdaptor.replaceChildren (   self,
  parent,
  startChildIndex,
  stopChildIndex,
  t 
)
Replace from start to stop child index of parent with t, which might
be a list.  Number of children may be different
after this call.

If parent is null, don't do anything; must be at root of overall tree.
Can't replace whatever points to the parent externally.  Do nothing.
def google.appengine._internal.antlr3.tree.TreeAdaptor.rulePostProcessing (   self,
  root 
)
Given the root of the subtree created for this rule, post process
it to do any simplifications or whatever you want.  A required
behavior is to convert ^(nil singleSubtree) to singleSubtree
as the setting of start/stop indexes relies on a single non-nil root
for non-flat trees.

Flat trees such as for lists like "idlist : ID+ ;" are left alone
unless there is only one ID.  For a list, the start/stop indexes
are set in the nil node.

This method is executed after all rule tree construction and right
before setTokenBoundaries().
def google.appengine._internal.antlr3.tree.TreeAdaptor.setChild (   self,
  t,
  i,
  child 
)
Set ith child (0..n-1) to t; t must be non-null and non-nil node
def google.appengine._internal.antlr3.tree.TreeAdaptor.setChildIndex (   self,
  t,
  index 
)
What index is this node in the child list? Range: 0..n-1
If your node type doesn't handle this, it's ok but the tree rewrites
in tree parsers need this functionality.
def google.appengine._internal.antlr3.tree.TreeAdaptor.setParent (   self,
  t,
  parent 
)
Who is the parent node of this node; if null, implies node is root.
If your node type doesn't handle this, it's ok but the tree rewrites
in tree parsers need this functionality.
def google.appengine._internal.antlr3.tree.TreeAdaptor.setText (   self,
  t,
  text 
)
Node constructors can set the text of a node
def google.appengine._internal.antlr3.tree.TreeAdaptor.setTokenBoundaries (   self,
  t,
  startToken,
  stopToken 
)
Where are the bounds in the input token stream for this node and
all children?  Each rule that creates AST nodes will call this
method right before returning.  Flat trees (i.e., lists) will
still usually have a nil root node just to hold the children list.
That node would contain the start/stop indexes then.
def google.appengine._internal.antlr3.tree.TreeAdaptor.setType (   self,
  t,
  type 
)
Node constructors can set the type of a node

The documentation for this class was generated from the following file: