polyglot.visit
Class TypeChecker

java.lang.Object
  polyglot.visit.NodeVisitor
      polyglot.visit.HaltingVisitor
          polyglot.visit.ErrorHandlingVisitor
              polyglot.visit.ContextVisitor
                  polyglot.visit.TypeChecker

All Implemented Interfaces:

java.lang.Cloneable, Copy

public class TypeChecker
extends ContextVisitor

Visitor which performs type checking on the AST.

Field Summary

Fields inherited from class polyglot.visit.ContextVisitor

context, outer

Fields inherited from class polyglot.visit.ErrorHandlingVisitor

error, job, nf, ts

Constructor Summary

TypeChecker(Job job, TypeSystem ts, NodeFactory nf)

Method Summary

protected NodeVisitor	enterCall(Node parent, Node n) Replaces the functionality of the enter() method; all sub-classes should over-ride this method instead of enter() if there is any chance of exceptions being generated.
protected Node	leaveCall(Node old, Node n, NodeVisitor v) Contains all of the functionality that can be done in the leave method, but allows SemanticExceptions to be thrown.

Methods inherited from class polyglot.visit.ContextVisitor

addDecls, begin, context, context, enter, enterScope, leave, superEnter

Methods inherited from class polyglot.visit.ErrorHandlingVisitor

catchErrors, enterCall, enterError, errorQueue, job, leaveCall, nodeFactory, typeSystem

Methods inherited from class polyglot.visit.HaltingVisitor

bypass, bypass, bypassChildren, copy, override, visitChildren

Methods inherited from class polyglot.visit.NodeVisitor

enter, finish, finish, leave, override, toString, visitEdge

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

TypeChecker

public TypeChecker(Job job,
                   TypeSystem ts,
                   NodeFactory nf)

Method Detail

enterCall

protected NodeVisitor enterCall(Node parent,
                                Node n)
                         throws SemanticException

Description copied from class: ErrorHandlingVisitor

Replaces the functionality of the enter() method; all sub-classes should over-ride this method instead of enter() if there is any chance of exceptions being generated. This method is the replacement for the enter() method, so that all of its subclasses gain the error handling capabilities of this visitor without having to rewrite it for the enter() for each sub-class. This method allows for a SemanticException to be thrown in the body, while enter() does not.

Overrides:

enterCall in class ErrorHandlingVisitor

n - The root of the subtree to be traversed.

Returns:

The ErrorHandlingVisitor which should be used to visit the children of n.

Throws:

SemanticException

See Also:

NodeVisitor.enter(Node, Node)

leaveCall

protected Node leaveCall(Node old,
                         Node n,
                         NodeVisitor v)
                  throws SemanticException

Description copied from class: ErrorHandlingVisitor

Contains all of the functionality that can be done in the leave method, but allows SemanticExceptions to be thrown. This method is in addition to the leave method, and allows the compiler writer to write code that can throw errors and let the polyglot infrastructure handle the exceptions.

Overrides:

leaveCall in class ErrorHandlingVisitor

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.

Throws:

SemanticException

See Also:

NodeVisitor.leave(Node, Node, NodeVisitor)