Package schrodinger :: Package application :: Package desmond :: Package antlr3 :: Module treewizard :: Class TreeWizard
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Class TreeWizard

object --+
         |
        TreeWizard

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.

Instance Methods [hide private]
 
__init__(self, adaptor=None, tokenNames=None, typeMap=None)
x.__init__(...) initializes x; see help(type(x)) for signature
 
getTokenType(self, tokenName)
Using the map of token names to token types, return the type.
 
create(self, pattern)
Create a tree or node from the indicated tree pattern that closely follows ANTLR tree grammar tree element syntax:
 
index(self, tree)
Walk the entire tree and make a node name to nodes mapping.
 
_index(self, t, m)
Do the work for index
 
find(self, tree, what)
Return a list of matching token.
 
_findTokenType(self, t, ttype)
Return a List of tree nodes with token type ttype
 
_findPattern(self, t, pattern)
Return a List of subtrees matching pattern.
 
visit(self, tree, what, visitor)
Visit every node in tree matching what, invoking the visitor.
 
_visitType(self, t, parent, childIndex, ttype, visitor)
Do the recursive work for visit
 
_visitPattern(self, tree, pattern, visitor)
For all subtrees that match the pattern, execute the visit action.
 
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.
 
_parse(self, t1, tpattern, labels)
Do the work for parse.
 
equals(self, t1, t2, adaptor=None)
Compare t1 and t2; return true if token types/text, structure match exactly.
 
_equals(self, t1, t2, adaptor)

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __str__, __subclasshook__

Properties [hide private]

Inherited from object: __class__

Method Details [hide private]

__init__(self, adaptor=None, tokenNames=None, typeMap=None)
(Constructor)

 

x.__init__(...) initializes x; see help(type(x)) for signature

Overrides: object.__init__
(inherited documentation)

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.

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.

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.

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.

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.

_parse(self, t1, tpattern, labels)

 

Do the work for parse. Check to see if the tpattern fits the structure and token types in t1. Check text if the pattern has text arguments on nodes. Fill labels map with pointers to nodes in tree matched against nodes in pattern with labels.

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)).