polyglot.ast
Class Node_c

java.lang.Object
  polyglot.ast.Node_c

All Implemented Interfaces:

java.lang.Cloneable, JL, Node, NodeOps, Copy

Direct Known Subclasses:

AmbPrefix_c, AmbQualifierNode_c, Id_c, Import_c, NodeList_c, PackageNode_c, SourceCollection_c, SourceFile_c, Term_c

public abstract class Node_c
extends java.lang.Object
implements Node

A Node represents an AST node. All AST nodes must implement this interface. Nodes should be immutable: methods which set fields of the node should copy the node, set the field in the copy, and then return the copy.

Field Summary

protected JL	del
protected boolean	error
protected Ext	ext
protected Position	position

Constructor Summary

Node_c(Position pos)

Method Summary

void	addDecls(Context c) Add any declarations to the context that should be in scope when visiting later sibling nodes.
Node	buildTypes(TypeBuilder tb) Collects classes, methods, and fields from the AST rooted at this node and constructs type objects for these.
NodeVisitor	buildTypesEnter(TypeBuilder tb) Collects classes, methods, and fields from the AST rooted at this node and constructs type objects for these.
Node	checkConstants(ConstantChecker cc) Check if the node is a compile-time constant.
Type	childExpectedType(Expr child, AscriptionVisitor av) Get the expected type of a child expression of this.
java.lang.Object	copy()
Node	copy(ExtensionInfo extInfo) Produce a copy of this node using the given ExtensionInfo.
Node	copy(NodeFactory nf) Produce a copy of this node using the given NodeFactory.
JL	del() Get the node's delegate.
Node	del(JL del) Set the delegate of the node.
Node	disambiguate(AmbiguityRemover ar) Remove any remaining ambiguities from the AST.
NodeVisitor	disambiguateEnter(AmbiguityRemover ar) Remove any remaining ambiguities from the AST.
Node	disambiguateOverride(Node parent, AmbiguityRemover ar) Disambiguate the AST.
void	dump(CodeWriter w) Dump the AST node for debugging purposes.
void	dump(java.io.OutputStream os) Dump the AST for debugging.
void	dump(java.io.Writer w) Dump the AST for debugging.
Context	enterChildScope(Node child, Context c) Push a new scope for visiting the child node child.
Context	enterScope(Context c) Push a new scope upon entering this node, and add any declarations to the context that should be in scope when visiting children of this node.
boolean	error() Return true if there an error in this node or its children.
Node	error(boolean flag)
Node	exceptionCheck(ExceptionChecker ec) Check that exceptions are properly propagated throughout the AST.
NodeVisitor	exceptionCheckEnter(ExceptionChecker ec) Check that exceptions are properly propagated throughout the AST.
Ext	ext() Get the node's extension.
Node	ext(Ext ext) Set the extension of the node.
Ext	ext(int n) Get the node's nth extension, n >= 1.
Node	ext(int n, Ext ext) Set the node's nth extension, n >= 1.
void	init(Node node) Initialize the back pointer to the node.
boolean	isDisambiguated()
boolean	isTypeChecked()
Node	node() Pointer back to the node we are delegating for, possibly this.
Position	position() Get the position of the node in the source file.
Node	position(Position position) Create a copy of the node with a new position.
void	prettyPrint(CodeWriter w, PrettyPrinter pp) Pretty-print the AST using the given CodeWriter.
void	prettyPrint(java.io.OutputStream os) Pretty-print the AST for debugging.
void	prettyPrint(java.io.Writer w) Pretty-print the AST for debugging.
void	print(Node child, CodeWriter w, PrettyPrinter pp)
void	printBlock(Node n, CodeWriter w, PrettyPrinter pp)
void	printSubStmt(Stmt stmt, CodeWriter w, PrettyPrinter pp)
java.util.List	throwTypes(TypeSystem ts) List of Types of exceptions that might get thrown.
java.lang.String	toString()
void	translate(CodeWriter w, Translator tr) Translate the AST using the given CodeWriter.
Node	typeCheck(TypeChecker tc) Type check the AST.
NodeVisitor	typeCheckEnter(TypeChecker tc) Type check the AST.
Node	typeCheckOverride(Node parent, TypeChecker tc) Type check the AST.
Node	visit(NodeVisitor v) Visit the node.
Node	visitChild(Node n, NodeVisitor v) Visit a single child of the node.
Node	visitChildren(NodeVisitor v) Visit the children of the node.
Node	visitEdge(Node parent, NodeVisitor v) Deprecated. Call Node.visitChild(Node, NodeVisitor) instead.
java.util.List	visitList(java.util.List l, NodeVisitor v) Visit all the elements of a list.

Methods inherited from class java.lang.Object

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

Field Detail

position

protected Position position

del

protected JL del

ext

protected Ext ext

error

protected boolean error

Constructor Detail

Node_c

public Node_c(Position pos)

Method Detail

init

public void init(Node node)

Description copied from interface: JL

Initialize the back pointer to the node.

Specified by:

init in interface JL

node

public Node node()

Description copied from interface: JL

Pointer back to the node we are delegating for, possibly this.

Specified by:

node in interface JL

del

public JL del()

Description copied from interface: Node

Get the node's delegate.

Specified by:

del in interface Node

del

public Node del(JL del)

Description copied from interface: Node

Set the delegate of the node.

Specified by:

del in interface Node

ext

public Ext ext(int n)

Description copied from interface: Node

Get the node's nth extension, n >= 1.

Specified by:

ext in interface Node

ext

public Node ext(int n,
                Ext ext)

Description copied from interface: Node

Set the node's nth extension, n >= 1.

Specified by:

ext in interface Node

ext

public Ext ext()

Description copied from interface: Node

Get the node's extension.

Specified by:

ext in interface Node

ext

public Node ext(Ext ext)

Description copied from interface: Node

Set the extension of the node.

Specified by:

ext in interface Node

copy

public java.lang.Object copy()

Specified by:

copy in interface Copy

position

public Position position()

Description copied from interface: Node

Get the position of the node in the source file. Returns null if the position is not set.

Specified by:

position in interface Node

position

public Node position(Position position)

Description copied from interface: Node

Create a copy of the node with a new position.

Specified by:

position in interface Node

isDisambiguated

public boolean isDisambiguated()

Specified by:

isDisambiguated in interface Node

Returns:

true if the all type information for the node (but not necessarily for the node's children) is unambiguous.

isTypeChecked

public boolean isTypeChecked()

Specified by:

isTypeChecked in interface Node

Returns:

true if all the type information for the node (but not necessarily for the node's children) has been computed.

error

public boolean error()

Description copied from interface: Node

Return true if there an error in this node or its children.

Specified by:

error in interface Node

error

public Node error(boolean flag)

Specified by:

error in interface Node

visitChild

public Node visitChild(Node n,
                       NodeVisitor v)

Description copied from interface: Node

Visit a single child of the node.

Specified by:

visitChild in interface Node

Parameters:

n - The child to visit.

v - The visitor which will traverse/rewrite the AST.

Returns:

The result of child.visit(v), or null if child was null.

visit

public Node visit(NodeVisitor v)

Description copied from interface: Node

Visit the node. This method is equivalent to visitEdge(null, v).

Specified by:

visit in interface Node

Parameters:

v - The visitor which will traverse/rewrite the AST.

Returns:

A new AST if a change was made, or this.

visitEdge

public Node visitEdge(Node parent,
                      NodeVisitor v)

Deprecated. Call Node.visitChild(Node, NodeVisitor) instead.

Description copied from interface: Node

Visit the node, passing in the node's parent. This method is called by a NodeVisitor to traverse the AST starting at this node. This method should call the override, enter, and leave methods of the visitor. The method may return a new version of the node.

Specified by:

visitEdge in interface Node

Parameters:

parent - The parent of this in the AST.

v - The visitor which will traverse/rewrite the AST.

Returns:

A new AST if a change was made, or this.

visitList

public java.util.List visitList(java.util.List l,
                                NodeVisitor v)

Visit all the elements of a list.

Specified by:

visitList in interface Node

Parameters:

l - The list to visit.

v - The visitor to use.

Returns:

A new list with each element from the old list replaced by the result of visiting that element. If l is a TypedList, the new list will also be typed with the same type as l. If l is null, null is returned.

visitChildren

public Node visitChildren(NodeVisitor v)

Description copied from interface: NodeOps

Visit the children of the node.

Specified by:

visitChildren in interface NodeOps

Parameters:

v - The visitor that will traverse/rewrite the AST.

Returns:

A new AST if a change was made, or this.

enterScope

public Context enterScope(Context c)

Push a new scope upon entering this node, and add any declarations to the context that should be in scope when visiting children of this node.

Specified by:

enterScope in interface NodeOps

Parameters:

c - the current Context

Returns:

the Context to be used for visiting this node.

enterChildScope

public Context enterChildScope(Node child,
                               Context c)

Push a new scope for visiting the child node child. The default behavior is to delegate the call to the child node, and let it add appropriate declarations that should be in scope. However, this method gives parent nodes have the ability to modify this behavior.

Specified by:

enterChildScope in interface NodeOps

Parameters:

child - the child node about to be entered.

c - the current Context

Returns:

the Context to be used for visiting node child

addDecls

public void addDecls(Context c)

Add any declarations to the context that should be in scope when visiting later sibling nodes.

Specified by:

addDecls in interface NodeOps

Parameters:

c - The context to which to add declarations.

buildTypesEnter

public NodeVisitor buildTypesEnter(TypeBuilder tb)
                            throws SemanticException

Description copied from interface: NodeOps

Collects classes, methods, and fields from the AST rooted at this node and constructs type objects for these. These type objects may be ambiguous. Inserts classes into the TypeSystem. This method is called by the enter() method of the visitor. The * method should perform work that should be done before visiting the children of the node. The method may return this or a new copy of the node on which visitChildren() and leave() will be invoked.

Specified by:

buildTypesEnter in interface NodeOps

Parameters:

tb - The visitor which adds new type objects to the TypeSystem.

Throws:

SemanticException

buildTypes

public Node buildTypes(TypeBuilder tb)
                throws SemanticException

Description copied from interface: NodeOps

Collects classes, methods, and fields from the AST rooted at this node and constructs type objects for these. These type objects may be ambiguous. Inserts classes into the TypeSystem. This method is called by the leave() method of the visitor. The method should perform work that should be done after visiting the children of the node. The method may return this or a new copy of the node which will be installed as a child of the node's parent.

Specified by:

buildTypes in interface NodeOps

Parameters:

tb - The visitor which adds new type objects to the TypeSystem.

Throws:

SemanticException

disambiguateOverride

public Node disambiguateOverride(Node parent,
                                 AmbiguityRemover ar)
                          throws SemanticException

Description copied from interface: NodeOps

Disambiguate the AST. This method is called by the override() method of the visitor. If this method returns non-null, the node's children will not be visited automatically. Thus, the method should check both the node this and it's children, usually by invoking visitChildren with tc or with another visitor, returning a non-null node. OR, the method should do nothing and simply return null to allow enter, visitChildren, and leave to be invoked on the node. The default implementation returns null. Overriding of this method is discouraged, but sometimes necessary.

Specified by:

disambiguateOverride in interface NodeOps

ar - The visitor which disambiguates.

Throws:

SemanticException

disambiguateEnter

public NodeVisitor disambiguateEnter(AmbiguityRemover ar)
                              throws SemanticException

Description copied from interface: NodeOps

Remove any remaining ambiguities from the AST. This method is called by the enter() method of the visitor. The * method should perform work that should be done before visiting the children of the node. The method may return this or a new copy of the node on which visitChildren() and leave() will be invoked.

Specified by:

disambiguateEnter in interface NodeOps

Parameters:

ar - The visitor which disambiguates.

Throws:

SemanticException

disambiguate

public Node disambiguate(AmbiguityRemover ar)
                  throws SemanticException

Description copied from interface: NodeOps

Remove any remaining ambiguities from the AST. This method is called by the leave() method of the visitor. The method should perform work that should be done after visiting the children of the node. The method may return this or a new copy of the node which will be installed as a child of the node's parent. The node should not assume that its children have been disambiguated. If it depends on a child being disambiguated, it may just return this without doing any work.

Specified by:

disambiguate in interface NodeOps

Parameters:

ar - The visitor which disambiguates.

Throws:

SemanticException

typeCheckOverride

public Node typeCheckOverride(Node parent,
                              TypeChecker tc)
                       throws SemanticException

Type check the AST.

Specified by:

typeCheckOverride in interface NodeOps

tc - The type checking visitor.

Throws:

SemanticException

typeCheckEnter

public NodeVisitor typeCheckEnter(TypeChecker tc)
                           throws SemanticException

Description copied from interface: NodeOps

Type check the AST. This method is called by the enter() method of the visitor. The * method should perform work that should be done before visiting the children of the node. The method may return this or a new copy of the node on which visitChildren() and leave() will be invoked.

Specified by:

typeCheckEnter in interface NodeOps

Parameters:

tc - The type checking visitor.

Throws:

SemanticException

typeCheck

public Node typeCheck(TypeChecker tc)
               throws SemanticException

Description copied from interface: NodeOps

Type check the AST. This method is called by the leave() method of the visitor. The method should perform work that should be done after visiting the children of the node. The method may return this or a new copy of the node which will be installed as a child of the node's parent.

Specified by:

typeCheck in interface NodeOps

Parameters:

tc - The type checking visitor.

Throws:

SemanticException

checkConstants

public Node checkConstants(ConstantChecker cc)
                    throws SemanticException

Description copied from interface: NodeOps

Check if the node is a compile-time constant. This method is called by the leave() method of the visitor. The method should perform work that should be done after visiting the children of the node. The method may return this or a new copy of the node which will be installed as a child of the node's parent.

Specified by:

checkConstants in interface NodeOps

Parameters:

cc - The constant checking visitor.

Throws:

SemanticException

childExpectedType

public Type childExpectedType(Expr child,
                              AscriptionVisitor av)

Description copied from interface: Node

Get the expected type of a child expression of this. The expected type is determined by the context in that the child occurs (e.g., for x = e, the expected type of e is the declared type of x. The expected type should impose the least constraints on the child's type that are allowed by the parent node.

Specified by:

childExpectedType in interface Node

Parameters:

child - A child expression of this node.

av - An ascription visitor.

Returns:

The expected type of child.

exceptionCheckEnter

public NodeVisitor exceptionCheckEnter(ExceptionChecker ec)
                                throws SemanticException

Description copied from interface: NodeOps

Check that exceptions are properly propagated throughout the AST. This method is called by the enter() method of the visitor. The * method should perform work that should be done before visiting the children of the node. The method may return this or a new copy of the node on which visitChildren() and leave() will be invoked.

Specified by:

exceptionCheckEnter in interface NodeOps

Parameters:

ec - The visitor.

Throws:

SemanticException

exceptionCheck

public Node exceptionCheck(ExceptionChecker ec)
                    throws SemanticException

Description copied from interface: NodeOps

Check that exceptions are properly propagated throughout the AST. This method is called by the leave() method of the visitor. The method should perform work that should be done after visiting the children of the node. The method may return this or a new copy of the node which will be installed as a child of the node's parent.

Specified by:

exceptionCheck in interface NodeOps

Parameters:

ec - The visitor.

Throws:

SemanticException

throwTypes

public java.util.List throwTypes(TypeSystem ts)

Description copied from interface: NodeOps

List of Types of exceptions that might get thrown. The result is not necessarily correct until after type checking.

Specified by:

throwTypes in interface NodeOps

dump

public void dump(java.io.OutputStream os)

Dump the AST for debugging.

Specified by:

dump in interface NodeOps

dump

public void dump(java.io.Writer w)

Dump the AST for debugging.

Specified by:

dump in interface NodeOps

prettyPrint

public void prettyPrint(java.io.OutputStream os)

Pretty-print the AST for debugging.

Specified by:

prettyPrint in interface NodeOps

prettyPrint

public void prettyPrint(java.io.Writer w)

Pretty-print the AST for debugging.

Specified by:

prettyPrint in interface NodeOps

prettyPrint

public void prettyPrint(CodeWriter w,
                        PrettyPrinter pp)

Pretty-print the AST using the given CodeWriter.

Specified by:

prettyPrint in interface NodeOps

Parameters:

w - The code writer to which to write.

pp - The pretty printer. This is not a visitor.

printBlock

public void printBlock(Node n,
                       CodeWriter w,
                       PrettyPrinter pp)

printSubStmt

public void printSubStmt(Stmt stmt,
                         CodeWriter w,
                         PrettyPrinter pp)

print

public void print(Node child,
                  CodeWriter w,
                  PrettyPrinter pp)

translate

public void translate(CodeWriter w,
                      Translator tr)

Translate the AST using the given CodeWriter.

Specified by:

translate in interface NodeOps

Parameters:

w - The code writer to which to write.

tr - The translation pass. This is not a visitor.

dump

public void dump(CodeWriter w)

Description copied from interface: Node

Dump the AST node for debugging purposes.

Specified by:

dump in interface Node

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

copy

public Node copy(NodeFactory nf)

Description copied from interface: NodeOps

Produce a copy of this node using the given NodeFactory.

Specified by:

copy in interface NodeOps

copy

public Node copy(ExtensionInfo extInfo)
          throws SemanticException

Description copied from interface: NodeOps

Produce a copy of this node using the given ExtensionInfo. This will typically be implemented by calling copy(NodeFactory nf), and then potentially copying over type information.

Specified by:

copy in interface NodeOps

Throws:

SemanticException - If the type information cannot be copied.