App Engine Python SDK  v1.6.9 rev.445
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Public Member Functions | Public Attributes | List of all members
google.appengine._internal.antlr3.treewizard.TreeWizard Class Reference
Inheritance diagram for google.appengine._internal.antlr3.treewizard.TreeWizard:

Public Member Functions

def __init__
 
def getTokenType
 
def create
 
def index
 
def find
 
def visit
 
def parse
 
def equals
 

Public Attributes

 adaptor
 
 tokenNameToTypeMap
 

Detailed Description

Build and navigate trees with this object.  Must know about the names
of tokens so you have to pass in a map or array of token names (from which
this class can build the map).  I.e., Token DECL means nothing unless the
class can translate it to a token type.

In order to create nodes and navigate, this class needs a TreeAdaptor.

This class can build a token type -> node index for repeated use or for
iterating over the various nodes with a particular type.

This class works in conjunction with the TreeAdaptor rather than moving
all this functionality into the adaptor.  An adaptor helps build and
navigate trees using methods.  This class helps you do it with string
patterns like "(A B C)".  You can create a tree from that pattern or
match subtrees against it.

Member Function Documentation

def google.appengine._internal.antlr3.treewizard.TreeWizard.create (   self,
  pattern 
)
Create a tree or node from the indicated tree pattern that closely
follows ANTLR tree grammar tree element syntax:

(root child1 ... child2).

You can also just pass in a node: ID

Any node can have a text argument: ID[foo]
(notice there are no quotes around foo--it's clear it's a string).

nil is a special name meaning "give me a nil node".  Useful for
making lists: (nil A B C) is a list of A B C.
def google.appengine._internal.antlr3.treewizard.TreeWizard.equals (   self,
  t1,
  t2,
  adaptor = None 
)
Compare t1 and t2; return true if token types/text, structure match
exactly.
The trees are examined in their entirety so that (A B) does not match
(A B C) nor (A (B C)).
def google.appengine._internal.antlr3.treewizard.TreeWizard.find (   self,
  tree,
  what 
)
Return a list of matching token.

what may either be an integer specifzing the token type to find or
a string with a pattern that must be matched.
def google.appengine._internal.antlr3.treewizard.TreeWizard.getTokenType (   self,
  tokenName 
)
Using the map of token names to token types, return the type.
def google.appengine._internal.antlr3.treewizard.TreeWizard.index (   self,
  tree 
)
Walk the entire tree and make a node name to nodes mapping.

For now, use recursion but later nonrecursive version may be
more efficient.  Returns a dict int -> list where the list is
of your AST node type.  The int is the token type of the node.
def google.appengine._internal.antlr3.treewizard.TreeWizard.parse (   self,
  t,
  pattern,
  labels = None 
)
Given a pattern like (ASSIGN %lhs:ID %rhs:.) with optional labels
on the various nodes and '.' (dot) as the node/subtree wildcard,
return true if the pattern matches and fill the labels Map with
the labels pointing at the appropriate nodes.  Return false if
the pattern is malformed or the tree does not match.

If a node specifies a text arg in pattern, then that must match
for that node in t.
def google.appengine._internal.antlr3.treewizard.TreeWizard.visit (   self,
  tree,
  what,
  visitor 
)
Visit every node in tree matching what, invoking the visitor.

If what is a string, it is parsed as a pattern and only matching
subtrees will be visited.
The implementation uses the root node of the pattern in combination
with visit(t, ttype, visitor) so nil-rooted patterns are not allowed.
Patterns with wildcard roots are also not allowed.

If what is an integer, it is used as a token type and visit will match
all nodes of that type (this is faster than the pattern match).
The labels arg of the visitor action method is never set (it's None)
since using a token type rather than a pattern doesn't let us set a
label.

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