polyglot.visit
Class FlattenVisitor
java.lang.Object
polyglot.visit.NodeVisitor
polyglot.visit.FlattenVisitor
- public class FlattenVisitor
- extends NodeVisitor
The FlattenVisitor flattens the AST,
|
Method Summary |
NodeVisitor |
enter(Node n)
When entering a BlockStatement, place a new StatementList
onto the stack |
Node |
leave(Node old,
Node n,
NodeVisitor v)
Flatten complex expressions within the AST |
protected static java.lang.String |
newID()
|
Node |
override(Node n)
Given a tree rooted at n, the visitor has the option of
overriding all traversal of the children of n. |
| Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait |
ts
protected TypeSystem ts
nf
protected NodeFactory nf
stack
protected java.util.LinkedList stack
noFlatten
protected Node noFlatten
FlattenVisitor
public FlattenVisitor(TypeSystem ts,
NodeFactory nf)
override
public Node override(Node n)
- Description copied from class:
NodeVisitor
- Given a tree rooted at
n, the visitor has the option of
overriding all traversal of the children of n. If no
changes were made to n and the visitor wishes to prevent
further traversal of the tree, then it should return n. If
changes were made to the subtree, then the visitor should return a
copy of n with appropriate changes. Finally, if the
visitor does not wish to override traversal of the subtree rooted at
n, then it should return null.
This method is typically called by the method
override(parent, n). If a subclass overrides the
method override(parent, n) then this method
may not be called.
- Overrides:
override in class NodeVisitor
- Parameters:
n - The root of the subtree to be traversed.
- Returns:
- A node if normal traversal is to stop,
null if it
is to continue.
newID
protected static java.lang.String newID()
enter
public NodeVisitor enter(Node n)
- When entering a BlockStatement, place a new StatementList
onto the stack
- Overrides:
enter in class NodeVisitor
- Parameters:
n - The root of the subtree to be traversed.
- Returns:
- The
NodeVisitor which should be used to visit the
children of n.
leave
public Node leave(Node old,
Node n,
NodeVisitor v)
- Flatten complex expressions within the AST
- Overrides:
leave in class NodeVisitor
- Parameters:
old - The original state of root of the current subtree.n - The current state of the root of the current subtree.v - The NodeVisitor object used to visit the children.
- Returns:
- The final result of the traversal of the tree rooted at
n.