org.mozilla.javascript.ast
Class FunctionNode

java.lang.Object
  org.mozilla.javascript.Node
      org.mozilla.javascript.ast.AstNode
          org.mozilla.javascript.ast.Jump
              org.mozilla.javascript.ast.Scope
                  org.mozilla.javascript.ast.ScriptNode
                      org.mozilla.javascript.ast.FunctionNode

All Implemented Interfaces:

java.lang.Comparable<AstNode>, java.lang.Iterable<Node>

public class FunctionNode
extends ScriptNode

A JavaScript function declaration or expression.

Node type is Token.FUNCTION.

FunctionDeclaration :
        function Identifier ( FormalParameterListopt ) { FunctionBody }
 FunctionExpression :
        function Identifieropt ( FormalParameterListopt ) { FunctionBody }
 FormalParameterList :
        Identifier
        FormalParameterList , Identifier
 FunctionBody :
        SourceElements
 Program :
        SourceElements
 SourceElements :
        SourceElement
        SourceElements SourceElement
 SourceElement :
        Statement
        FunctionDeclaration

JavaScript 1.8 introduces "function closures" of the form

function ([params] ) Expression

In this case the FunctionNode node will have no body but will have an expression.

Nested Class Summary

static class

FunctionNode.Form

Nested classes/interfaces inherited from class org.mozilla.javascript.ast.AstNode

AstNode.DebugPrintVisitor, AstNode.PositionComparator

Nested classes/interfaces inherited from class org.mozilla.javascript.Node

Node.NodeIterator

Field Summary

static int	FUNCTION_EXPRESSION
static int	FUNCTION_EXPRESSION_STATEMENT
static int	FUNCTION_STATEMENT There are three types of functions that can be defined.

Fields inherited from class org.mozilla.javascript.ast.Scope

parentScope, symbolTable, top

Fields inherited from class org.mozilla.javascript.ast.Jump

target

Fields inherited from class org.mozilla.javascript.ast.AstNode

length, parent, position

Fields inherited from class org.mozilla.javascript.Node

ATTRIBUTE_FLAG, BOTH, CASEARRAY_PROP, CATCH_SCOPE_PROP, CONTROL_BLOCK_PROP, DECR_FLAG, DESCENDANTS_FLAG, DESTRUCTURING_ARRAY_LENGTH, DESTRUCTURING_NAMES, DESTRUCTURING_PARAMS, DESTRUCTURING_SHORTHAND, DIRECTCALL_PROP, END_DROPS_OFF, END_RETURNS, END_RETURNS_VALUE, END_UNREACHED, END_YIELDS, EXPRESSION_CLOSURE_PROP, first, FUNCTION_PROP, GENERATOR_END_PROP, INCRDECR_PROP, ISNUMBER_PROP, JSDOC_PROP, LABEL_ID_PROP, last, LAST_PROP, LEFT, lineno, LOCAL_BLOCK_PROP, LOCAL_PROP, MEMBER_TYPE_PROP, NAME_PROP, next, NON_SPECIALCALL, OBJECT_IDS_PROP, PARENTHESIZED_PROP, POST_FLAG, PROPERTY_FLAG, propListHead, REGEXP_PROP, RIGHT, SKIP_INDEXES_PROP, SPECIALCALL_EVAL, SPECIALCALL_PROP, SPECIALCALL_WITH, TARGETBLOCK_PROP, type, VARIABLE_PROP

Constructor Summary

FunctionNode()

FunctionNode(int pos)

FunctionNode(int pos, Name name)

Method Summary

int	addFunction(FunctionNode fnNode) Adds a FunctionNode to the functions table for codegen.
void	addLiveLocals(Node node, int[] locals)
void	addParam(AstNode param) Adds a parameter to the function parameter list.
void	addResumptionPoint(Node target)
AstNode	getBody() Returns function body.
Name	getFunctionName() Returns function name
int	getFunctionType() Returns the function type (statement, expr, statement expr)
java.util.Map<Node,int[]>	getLiveLocals()
int	getLp() Returns left paren position, -1 if missing
AstNode	getMemberExprNode()
java.lang.String	getName() Returns the function name as a string
java.util.List<AstNode>	getParams() Returns the function parameter list
java.util.List<Node>	getResumptionPoints()
int	getRp() Returns right paren position, -1 if missing
boolean	isExpressionClosure() Returns whether this is a 1.8 function closure
boolean	isGenerator()
boolean	isGetter()
boolean	isGetterOrSetter()
boolean	isParam(AstNode node) Returns true if the specified AstNode node is a parameter of this Function node.
boolean	isSetter()
boolean	requiresActivation() Return true if this function requires an Ecma-262 Activation object.
void	setBody(AstNode body) Sets function body, and sets its parent to this node.
void	setFunctionIsGetter()
void	setFunctionIsSetter()
void	setFunctionName(Name name) Sets function name, and sets its parent to this node.
void	setFunctionType(int type)
void	setIsExpressionClosure(boolean isExpressionClosure) Sets whether this is a 1.8 function closure
void	setIsGenerator()
void	setLp(int lp) Sets left paren position
void	setMemberExprNode(AstNode node) Rhino supports a nonstandard Ecma extension that allows you to say, for instance, function a.b.c(arg1, arg) {...}, and it will be rewritten at codegen time to: a.b.c = function(arg1, arg2) {...} If we detect an expression other than a simple Name in the position where a function name was expected, we record that expression here.
void	setParams(java.util.List<AstNode> params) Sets the function parameter list, and sets the parent for each element of the list.
void	setParens(int lp, int rp) Sets both paren positions
void	setRequiresActivation()
void	setRp(int rp) Sets right paren position
java.lang.String	toSource(int depth) Emits source code for this node.
void	visit(NodeVisitor v) Visits this node, the function name node if supplied, the parameters, and the body.

Methods inherited from class org.mozilla.javascript.ast.ScriptNode

addRegExp, flattenSymbolTable, getBaseLineno, getCompilerData, getEncodedSource, getEncodedSourceEnd, getEncodedSourceStart, getEndLineno, getFunctionCount, getFunctionNode, getFunctions, getIndexForNameNode, getNextTempName, getParamAndVarConst, getParamAndVarCount, getParamAndVarNames, getParamCount, getParamOrVarName, getRegexpCount, getRegexpFlags, getRegexpString, getSourceName, getSymbols, setBaseLineno, setCompilerData, setEncodedSource, setEncodedSourceBounds, setEncodedSourceEnd, setEncodedSourceStart, setEndLineno, setSourceName, setSymbols

Methods inherited from class org.mozilla.javascript.ast.Scope

addChildScope, clearParentScope, getChildScopes, getDefiningScope, getParentScope, getStatements, getSymbol, getSymbolTable, getTop, joinScopes, putSymbol, replaceWith, setParentScope, setSymbolTable, setTop, splitScope

Methods inherited from class org.mozilla.javascript.ast.Jump

getContinue, getDefault, getFinally, getJumpStatement, getLoop, setContinue, setDefault, setFinally, setJumpStatement, setLoop

Methods inherited from class org.mozilla.javascript.ast.AstNode

addChild, assertNotNull, codeBug, compareTo, debugPrint, depth, getAbsolutePosition, getAstRoot, getEnclosingFunction, getEnclosingScope, getLength, getLineno, getParent, getPosition, hasSideEffects, makeIndent, operatorToString, printList, setBounds, setLength, setParent, setPosition, setRelative, shortName, toSource

Methods inherited from class org.mozilla.javascript.Node

addChildAfter, addChildBefore, addChildrenToBack, addChildrenToFront, addChildToBack, addChildToFront, getChildBefore, getDouble, getExistingIntProp, getFirstChild, getIntProp, getJsDoc, getJsDocNode, getLastChild, getLastSibling, getNext, getProp, getScope, getString, getType, hasChildren, hasConsistentReturnUsage, iterator, labelId, labelId, newNumber, newString, newString, newTarget, putIntProp, putProp, removeChild, removeChildren, removeProp, replaceChild, replaceChildAfter, resetTargets, setDouble, setJsDocNode, setLineno, setScope, setString, setType, toString, toStringTree

Methods inherited from class java.lang.Object

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

Field Detail

FUNCTION_STATEMENT

public static final int FUNCTION_STATEMENT

There are three types of functions that can be defined. The first is a function statement. This is a function appearing as a top-level statement (i.e., not nested inside some other statement) in either a script or a function.

The second is a function expression, which is a function appearing in an expression except for the third type, which is...

The third type is a function expression where the expression is the top-level expression in an expression statement.

The three types of functions have different treatment and must be distinguished.

See Also:

Constant Field Values

FUNCTION_EXPRESSION

public static final int FUNCTION_EXPRESSION

See Also:

Constant Field Values

FUNCTION_EXPRESSION_STATEMENT

public static final int FUNCTION_EXPRESSION_STATEMENT

See Also:

Constant Field Values

Constructor Detail

FunctionNode

public FunctionNode()

FunctionNode

public FunctionNode(int pos)

FunctionNode

public FunctionNode(int pos,
                    Name name)

Method Detail

getFunctionName

public Name getFunctionName()

Returns function name

Returns:

function name, null for anonymous functions

setFunctionName

public void setFunctionName(Name name)

Sets function name, and sets its parent to this node.

Parameters:

name - function name, null for anonymous functions

getName

public java.lang.String getName()

Returns the function name as a string

Returns:

the function name, "" if anonymous

getParams

public java.util.List<AstNode> getParams()

Returns the function parameter list

Returns:

the function parameter list. Returns an immutable empty list if there are no parameters.

setParams

public void setParams(java.util.List<AstNode> params)

Sets the function parameter list, and sets the parent for each element of the list.

Parameters:

params - the function parameter list, or null if no params

addParam

public void addParam(AstNode param)

Adds a parameter to the function parameter list. Sets the parent of the param node to this node.

Parameters:

param - the parameter

Throws:

java.lang.IllegalArgumentException - if param is null

isParam

public boolean isParam(AstNode node)

Returns true if the specified AstNode node is a parameter of this Function node. This provides a way during AST traversal to disambiguate the function name node from the parameter nodes.

getBody

public AstNode getBody()

Returns function body. Normally a Block, but can be a plain AstNode if it's a function closure.

Returns:

the body. Can be null only if the AST is malformed.

setBody

public void setBody(AstNode body)

Sets function body, and sets its parent to this node. Also sets the encoded source bounds based on the body bounds. Assumes the function node absolute position has already been set, and the body node's absolute position and length are set.

Parameters:

body - function body. Its parent is set to this node, and its position is updated to be relative to this node.

Throws:

java.lang.IllegalArgumentException - if body is null

getLp

public int getLp()

Returns left paren position, -1 if missing

setLp

public void setLp(int lp)

Sets left paren position

getRp

public int getRp()

Returns right paren position, -1 if missing

setRp

public void setRp(int rp)

Sets right paren position

setParens

public void setParens(int lp,
                      int rp)

Sets both paren positions

isExpressionClosure

public boolean isExpressionClosure()

Returns whether this is a 1.8 function closure

setIsExpressionClosure

public void setIsExpressionClosure(boolean isExpressionClosure)

Sets whether this is a 1.8 function closure

requiresActivation

public boolean requiresActivation()

Return true if this function requires an Ecma-262 Activation object. The Activation object is implemented by NativeCall, and is fairly expensive to create, so when possible, the interpreter attempts to use a plain call frame instead.

Returns:

true if this function needs activation. It could be needed if there is a lexical closure, or in a number of other situations.

setRequiresActivation

public void setRequiresActivation()

isGenerator

public boolean isGenerator()

setIsGenerator

public void setIsGenerator()

addResumptionPoint

public void addResumptionPoint(Node target)

getResumptionPoints

public java.util.List<Node> getResumptionPoints()

getLiveLocals

public java.util.Map<Node,int[]> getLiveLocals()

addLiveLocals

public void addLiveLocals(Node node,
                          int[] locals)

addFunction

public int addFunction(FunctionNode fnNode)

Description copied from class: ScriptNode

Adds a FunctionNode to the functions table for codegen. Does not set the parent of the node.

Overrides:

addFunction in class ScriptNode

Returns:

the index of the function within its parent

getFunctionType

public int getFunctionType()

Returns the function type (statement, expr, statement expr)

setFunctionType

public void setFunctionType(int type)

isGetterOrSetter

public boolean isGetterOrSetter()

isGetter

public boolean isGetter()

isSetter

public boolean isSetter()

setFunctionIsGetter

public void setFunctionIsGetter()

setFunctionIsSetter

public void setFunctionIsSetter()

setMemberExprNode

public void setMemberExprNode(AstNode node)

Rhino supports a nonstandard Ecma extension that allows you to say, for instance, function a.b.c(arg1, arg) {...}, and it will be rewritten at codegen time to: a.b.c = function(arg1, arg2) {...} If we detect an expression other than a simple Name in the position where a function name was expected, we record that expression here.

This extension is only available by setting the CompilerEnv option "isAllowMemberExprAsFunctionName" in the Parser.

getMemberExprNode

public AstNode getMemberExprNode()

toSource

public java.lang.String toSource(int depth)

Description copied from class: AstNode

Emits source code for this node. Callee is responsible for calling this function recursively on children, incrementing indent as appropriate.

Note: if the parser was in error-recovery mode, some AST nodes may have null children that are expected to be non-null when no errors are present. In this situation, the behavior of the toSource method is undefined: toSource implementations may assume that the AST node is error-free, since it is intended to be invoked only at runtime after a successful parse.

Overrides:

toSource in class Scope

Parameters:

depth - the current recursion depth, typically beginning at 0 when called on the root node.

visit

public void visit(NodeVisitor v)

Visits this node, the function name node if supplied, the parameters, and the body. If there is a member-expr node, it is visited last.

Overrides:

visit in class ScriptNode

Parameters:

v - the object to call with this node and its children