Recent builds of the standalone SpiderMonkey shell include a reflection of the SpiderMonkey parser, made available as a JavaScript API. This makes it easier to write tools in JavaScript that manipulate JavaScript source programs, such as syntax highlighters, static analyses, translators, compilers, obfuscators, etc.
NOTE: This page describes SpiderMonkey-specific behavior and might be incomplete. Visit ESTree spec for a community AST standard that includes latest ECMAScript features and is backward-compatible with SpiderMonkey format.
Example:
> var expr = Reflect.parse("obj.foo + 42").body[0].expression > expr.left.property ({loc:null, type:"Identifier", name:"foo"}) > expr.right ({loc:{source:null, start:{line:1, column:10}, end:{line:1, column:12}}, type:"Literal", value:42})
It is also available since Firefox 7; it can be imported into the global object via:
Components.utils.import("resource://gre/modules/reflect.jsm")
or into a specified object via:
Components.utils.import("resource://gre/modules/reflect.jsm", obj)
Built-in objects
Whether in SpiderMonkey shell or Firefox (after importing), the global singleton object Reflect
currently contains just the parse
method.
Properties of the Reflect
object
The Reflect
object currently consists of a single method.
Reflect.parse(src[, options])
Coerces src to a string and parses the result as a JavaScript program. By default, the parsing returns a Program object (see below) representing the parsed abstract syntax tree (AST).
Additional options may be provided via the options object, which can include any of the following properties:
loc | Boolean | Default: true |
When loc is true, the parser includes source location information in the returned AST nodes. | ||
source | String | Default: null |
A description of the input source; typically a filename, path, or URL. This string is not meaningful to the parsing process, but is produced as part of the source location information in the returned AST nodes. | ||
line | Number | Default: 1 |
The initial line number to use for source location information. | ||
builder | Builder | Default: null |
A builder object, which can be used to produce AST nodes in custom data formats. The expected callback methods are described under Builder Objects. |
If parsing fails due to a syntax error, an instance of SyntaxError
is thrown. The syntax error object thrown by Reflect.parse()
has the same message
property as the syntax error that would be thrown by eval(src)
. The lineNumber
and fileName
properties of the syntax error object indicate the source location of the syntax error.
Node objects
By default, Reflect.parse()
produces Node objects, which are plain JavaScript objects (i.e., their prototype derives from the standard Object
prototype). All node types implement the following interface:
interface Node { type: string; loc: SourceLocation | null; }
The type
field is a string representing the AST variant type. Each subtype of Node is documented below with the specific string of its type
field. You can use this field to determine which interface a node implements.
The loc
field represents the source location information of the node. If the parser produced no information about the node's source location, the field is null
; otherwise it is an object consisting of a start position (the position of the first character of the parsed source region) and an end position (the position of the first character after the parsed source region):
interface SourceLocation { source: string | null; start: Position; end: Position; }
Each Position
object consists of a line
number (1-indexed) and a column
number (0-indexed):
interface Position { line: uint32 >= 1; column: uint32 >= 0; }
Programs
interface Program <: Node { type: "Program"; body: [ Statement ]; }
A complete program source tree.
Functions
interface Function <: Node { id: Identifier | null; params: [ Pattern ]; defaults: [ Expression ]; rest: Identifier | null; body: BlockStatement | Expression; generator: boolean; expression: boolean; }
A function declaration or expression. The body
of the function may be a block statement, or in the case of an expression closure, an expression.
If the generator
flag is true
, the function is a generator function, i.e., contains a yield
expression in its body (other than in a nested function).
If the expression
flag is true
, the function is an expression closure and the body
field is an expression.
Statements
interface Statement <: Node { }
Any statement.
interface EmptyStatement <: Statement { type: "EmptyStatement"; }
An empty statement, i.e., a solitary semicolon.
interface BlockStatement <: Statement { type: "BlockStatement"; body: [ Statement ]; }
A block statement, i.e., a sequence of statements surrounded by braces.
interface ExpressionStatement <: Statement { type: "ExpressionStatement"; expression: Expression; }
An expression statement, i.e., a statement consisting of a single expression.
interface IfStatement <: Statement { type: "IfStatement"; test: Expression; consequent: Statement; alternate: Statement | null; }
An if
statement.
interface LabeledStatement <: Statement { type: "LabeledStatement"; label: Identifier; body: Statement; }
A labeled statement, i.e., a statement prefixed by a break
/continue
label.
interface BreakStatement <: Statement { type: "BreakStatement"; label: Identifier | null; }
A break
statement.
interface ContinueStatement <: Statement { type: "ContinueStatement"; label: Identifier | null; }
A continue
statement.
interface WithStatement <: Statement { type: "WithStatement"; object: Expression; body: Statement; }
A with
statement.
interface SwitchStatement <: Statement { type: "SwitchStatement"; discriminant: Expression; cases: [ SwitchCase ]; lexical: boolean; }
A switch
statement. The lexical flag is metadata indicating whether the switch
statement contains any unnested let
declarations (and therefore introduces a new lexical scope).
interface ReturnStatement <: Statement { type: "ReturnStatement"; argument: Expression | null; }
A return
statement.
interface ThrowStatement <: Statement { type: "ThrowStatement"; argument: Expression; }
A throw
statement.
interface TryStatement <: Statement { type: "TryStatement"; block: BlockStatement; handler: CatchClause | null; guardedHandlers: [ CatchClause ]; finalizer: BlockStatement | null; }
A try
statement.
catch
clauses are SpiderMonkey-specific.interface WhileStatement <: Statement { type: "WhileStatement"; test: Expression; body: Statement; }
A while
statement.
interface DoWhileStatement <: Statement { type: "DoWhileStatement"; body: Statement; test: Expression; }
A do
/while
statement.
interface ForStatement <: Statement { type: "ForStatement"; init: VariableDeclaration | Expression | null; test: Expression | null; update: Expression | null; body: Statement; }
A for
statement.
interface ForInStatement <: Statement { type: "ForInStatement"; left: VariableDeclaration | Expression; right: Expression; body: Statement; each: boolean; }
A for
/in
statement, or, if each
is true
, a for each
/in
statement.
for each
form is SpiderMonkey-specific.interface ForOfStatement <: Statement { type: "ForOfStatement"; left: VariableDeclaration | Expression; right: Expression; body: Statement; }
A for
/of
statement.
interface LetStatement <: Statement { type: "LetStatement"; head: [ VariableDeclarator ]; body: Statement; }
A let
statement.
let
statement form is SpiderMonkey-specific.interface DebuggerStatement <: Statement { type: "DebuggerStatement"; }
A debugger
statement.
debugger
statement is new in ECMAScript 5th edition, although SpiderMonkey has supported it for years.Declarations
interface Declaration <: Statement { }
Any declaration node. Note that declarations are considered statements; this is because declarations can appear in any statement context in the language recognized by the SpiderMonkey parser.
interface FunctionDeclaration <: Function, Declaration { type: "FunctionDeclaration"; id: Identifier; params: [ Pattern ]; defaults: [ Expression ]; rest: Identifier | null; body: BlockStatement | Expression; generator: boolean; expression: boolean; }
A function declaration.
id
field cannot be null
.interface VariableDeclaration <: Declaration { type: "VariableDeclaration"; declarations: [ VariableDeclarator ]; kind: "var" | "let" | "const"; }
A variable declaration, via one of var
, let
, or const
.
interface VariableDeclarator <: Node { type: "VariableDeclarator"; id: Pattern; init: Expression | null; }
A variable declarator.
id
field cannot be null
.let
and const
are SpiderMonkey-specific.Expressions
interface Expression <: Node, Pattern { }
Any expression node. Since the left-hand side of an assignment may be any expression in general, an expression can also be a pattern.
interface ThisExpression <: Expression { type: "ThisExpression"; }
A this
expression.
interface ArrayExpression <: Expression { type: "ArrayExpression"; elements: [ Expression | null ]; }
An array expression.
interface ObjectExpression <: Expression { type: "ObjectExpression"; properties: [ Property ]; }
An object expression.
interface Property <: Node { type: "Property"; key: Literal | Identifier; value: Expression; kind: "init" | "get" | "set"; }
A literal property in an object expression can have either a string or number as its value
. Ordinary property initializers have a kind
value "init"
; getters and setters have the kind
values "get"
and "set"
, respectively.
interface FunctionExpression <: Function, Expression { type: "FunctionExpression"; id: Identifier | null; params: [ Pattern ]; defaults: [ Expression ]; rest: Identifier | null; body: BlockStatement | Expression; generator: boolean; expression: boolean; }
A function expression.
interface ArrowExpression <: Function, Expression { type: "ArrowExpression"; params: [ Pattern ]; defaults: [ Expression ]; rest: Identifier | null; body: BlockStatement | Expression; generator: boolean; expression: boolean; }
A fat arrow function expression, i.e., `let foo = (bar) => { /* body */ }`.
interface SequenceExpression <: Expression { type: "SequenceExpression"; expressions: [ Expression ]; }
A sequence expression, i.e., a comma-separated sequence of expressions.
interface UnaryExpression <: Expression { type: "UnaryExpression"; operator: UnaryOperator; prefix: boolean; argument: Expression; }
A unary operator expression.
interface BinaryExpression <: Expression { type: "BinaryExpression"; operator: BinaryOperator; left: Expression; right: Expression; }
A binary operator expression.
interface AssignmentExpression <: Expression { type: "AssignmentExpression"; operator: AssignmentOperator; left: Pattern; right: Expression; }
An assignment operator expression.
interface UpdateExpression <: Expression { type: "UpdateExpression"; operator: UpdateOperator; argument: Expression; prefix: boolean; }
An update (increment or decrement) operator expression.
interface LogicalExpression <: Expression { type: "LogicalExpression"; operator: LogicalOperator; left: Expression; right: Expression; }
A logical operator expression.
interface ConditionalExpression <: Expression { type: "ConditionalExpression"; test: Expression; alternate: Expression; consequent: Expression; }
A conditional expression, i.e., a ternary ?
/:
expression.
interface NewExpression <: Expression { type: "NewExpression"; callee: Expression; arguments: [ Expression ]; }
A new
expression.
interface CallExpression <: Expression { type: "CallExpression"; callee: Expression; arguments: [ Expression ]; }
A function or method call expression.
interface MemberExpression <: Expression { type: "MemberExpression"; object: Expression; property: Identifier | Expression; computed: boolean; }
A member expression. If computed === true
, the node corresponds to a computed e1[e2]
expression and property is an Expression
. If computed === false
, the node corresponds to a static e1.x
expression and property is an Identifier
.
interface YieldExpression <: Expression { type: "YieldExpression"; argument: Expression | null; }
A yield
expression.
yield
expressions are SpiderMonkey-specific.interface ComprehensionExpression <: Expression { type: "ComprehensionExpression"; body: Expression; blocks: [ ComprehensionBlock | ComprehensionIf ]; filter: Expression | null; }
An array comprehension. The blocks
array corresponds to the sequence of for
and for each
blocks. The optional filter
expression corresponds to the final if
clause, if present.
interface GeneratorExpression <: Expression { type: "GeneratorExpression"; body: Expression; blocks: [ ComprehensionBlock | ComprehensionIf ]; filter: Expression | null; }
A generator expression. As with array comprehensions, the blocks
array corresponds to the sequence of for
and for each
blocks, and the optional filter
expression corresponds to the final if
clause, if present.
interface GraphExpression <: Expression { type: "GraphExpression"; index: uint32; expression: Literal; }
A graph expression, aka "sharp literal," such as #1={ self: #1# }
.
interface GraphIndexExpression <: Expression { type: "GraphIndexExpression"; index: uint32; }
A graph index expression, aka "sharp variable," such as #1#
.
interface LetExpression <: Expression { type: "LetExpression"; head: [ VariableDeclarator ]; body: Expression; }
A let
expression.
let
expression form is SpiderMonkey-specific.Patterns
interface Pattern <: Node { }
JavaScript 1.7 introduced destructuring assignment and binding forms. All binding forms (such as function parameters, variable declarations, and catch
block headers) accept array and object destructuring patterns in addition to plain identifiers. The left-hand sides of assignment expressions can be arbitrary expressions, but in the case where the expression is an object or array literal, it is interpreted by SpiderMonkey as a destructuring pattern.
Since the left-hand side of an assignment can in general be any expression, in an assignment context, a pattern can be any expression. In binding positions (such as function parameters, variable declarations, and catch
headers), patterns can only be identifiers in the base case, not arbitrary expressions.
interface ObjectPattern <: Pattern { type: "ObjectPattern"; properties: [ { key: Literal | Identifier, value: Pattern } ]; }
An object-destructuring pattern. A literal property in an object pattern can have either a string or number as its value
.
interface ArrayPattern <: Pattern { type: "ArrayPattern"; elements: [ Pattern | null ]; }
An array-destructuring pattern.
Clauses
interface SwitchCase <: Node { type: "SwitchCase"; test: Expression | null; consequent: [ Statement ]; }
A case
(if test
is an Expression
) or default
(if test === null
) clause in the body of a switch
statement.
interface CatchClause <: Node { type: "CatchClause"; param: Pattern; guard: Expression | null; body: BlockStatement; }
A catch
clause following a try
block. The optional guard
property corresponds to the optional expression guard on the bound variable.
interface ComprehensionBlock <: Node { type: "ComprehensionBlock"; left: Pattern; right: Expression; each: boolean; }
A for
or for each
block in an array comprehension or generator expression.
interface ComprehensionIf <: Node { type: "ComprehensionIf"; test: Expression; }
An if
filter in an array comprehension or generator filter.
Miscellaneous
interface Identifier <: Node, Expression, Pattern { type: "Identifier"; name: string; }
An identifier. Note that an identifier may be an expression or a destructuring pattern.
interface Literal <: Node, Expression { type: "Literal"; value: string | boolean | null | number | RegExp; }
A literal token. Note that a literal can be an expression.
enum UnaryOperator { "-" | "+" | "!" | "~" | "typeof" | "void" | "delete" }
A unary operator token.
enum BinaryOperator { "==" | "!=" | "===" | "!==" | "<" | "<=" | ">" | ">=" | "<<" | ">>" | ">>>" | "+" | "-" | "*" | "/" | "%" | "|" | "^" | "&" | "in" | "instanceof" | ".." }
A binary operator token.
..
operator is E4X-specific.enum LogicalOperator { "||" | "&&" }
A logical operator token.
enum AssignmentOperator { "=" | "+=" | "-=" | "*=" | "/=" | "%=" | "<<=" | ">>=" | ">>>=" | "|=" | "^=" | "&=" }
An assignment operator token.
enum UpdateOperator { "++" | "--" }
An update (increment or decrement) operator token.
E4X
This section describes node types that are provided for E4X support. E4X has since been removed as of Gecko 21.
Obsolete
This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
Declarations
interface XMLDefaultDeclaration <: Declaration { type: "XMLDefaultDeclaration"; namespace: Expression; }
A default xml namespace
declaration.
Expressions
interface XMLAnyName <: Expression { type: "XMLAnyName"; }
The special E4X wildcard pseudo-identifier *
.
interface XMLQualifiedIdentifier <: Expression { type: "XMLQualifiedIdentifier"; left: Identifier | XMLAnyName; right: Identifier | Expression; computed: boolean; }
An E4X qualified identifier, i.e., a pseudo-identifier using the namespace separator ::
. If the qualified identifier has a computed name (i.e., the id::[expr]
form), then computed
is true
and the right
property is an expression.
interface XMLFunctionQualifiedIdentifier <: Expression { type: "XMLFunctionQualifiedIdentifier"; right: Identifier | Expression; computed: boolean; }
An E4X identifier qualified by the function
keyword, e.g., function::id
.
function
-qualified identifiers are SpiderMonkey-specific.interface XMLAttributeSelector <: Expression { type: "XMLAttributeSelector"; attribute: Expression; }
An E4X attribute selector expression, i.e., an @
expression.
interface XMLFilterExpression <: Expression { type: "XMLFilterExpression"; left: Expression; right: Expression; }
An E4X list filter expression, i.e., an expression of the form expr.(expr)
.
interface XMLElement <: XML, Expression { type: "XMLElement"; contents: [ XML ]; }
An E4X literal representing a single XML element.
interface XMLList <: XML, Expression { type: "XMLList"; contents: [ XML ]; }
An E4X literal representing a list of XML elements.
XML
interface XML <: Node { }
XML data.
interface XMLEscape <: XML { type: "XMLEscape"; expression: Expression; }
XML data with an escaped JavaScript expression.
interface XMLText <: XML { type: "XMLText"; text: string; }
Literal XML text.
interface XMLStartTag <: XML { type: "XMLStartTag"; contents: [ XML ]; }
An XML start tag.
interface XMLEndTag <: XML { type: "XMLEndTag"; contents: [ XML ]; }
An XML end tag.
interface XMLPointTag <: XML { type: "XMLPointTag"; contents: [ XML ]; }
An XML point tag.
interface XMLName <: XML { type: "XMLName"; contents: string | [ XML ]; }
An XML name.
interface XMLAttribute <: XML { type: "XMLAttribute"; value: string; }
An XML attribute value.
interface XMLCdata <: XML { type: "XMLCdata"; contents: string; }
An XML CDATA node.
interface XMLComment <: XML { type: "XMLComment"; contents: string; }
An XML comment.
interface XMLProcessingInstruction <: XML { type: "XMLProcessingInstruction"; target: string; contents: string | null; }
An XML processing instruction.
Builder objects
The optional builder
parameter to Reflect.parse()
makes it possible to construct user-specified data from the parser, rather than the default Node
objects. Builder objects may contain any of the callback methods described in this section.
Each callback can produce any custom, user-defined datatype; these are referred to below as CustomExpression
, CustomStatement
, etc.
null
for optional nodes, it is recommended that user-defined datatypes not use null
as a representation of an AST node.If the loc
option is enabled (see the Reflect.parse() options above), then each callback is provided with the source location information of the parsed node as an extra parameter.
All builder callbacks are optional. When a callback is missing, the default format is used, but the provided builder methods are still used recursively for sub-nodes.
Programs
program(body[, loc])
body: [ CustomStatement ] loc: SourceLocation
Returns: CustomProgram
Callback to produce a custom program node.
Statements
emptyStatement([loc])
loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom empty statement node.
blockStatement(body[, loc])
body: CustomStatement loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom block statement node.
expressionStatement(expr[, loc])
expr: CustomExpression loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom expression statement node.
labeledStatement(label, body[, loc])
label: CustomIdentifier body: CustomStatement loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom labeled statement node.
ifStatement(test, cons, alt[, loc])
test: CustomExpression cons: CustomStatement alt: CustomStatement | null loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom if
statement node.
switchStatement(disc, cases, isLexical[, loc])
disc: CustomExpression cases: [ CustomSwitchCase ] isLexical: boolean loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom switch
statement node. The isLexical
flag is metadata indicating whether the switch
statement contains any unnested let
declarations (and therefore introduces a new lexical scope).
whileStatement(test, body[, loc])
test: CustomExpression body: CustomStatement loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom while
statement node.
doWhileStatement(body, test[, loc])
body: CustomStatement test: CustomExpression loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom do
-while
statement node.
forStatement(init, test, update, body[, loc])
init: CustomVariableDeclaration | CustomExpression | null test: CustomExpression | null update: CustomExpression | null body: CustomStatement loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom for
statement node.
forInStatement(left, right, body, isForEach[, loc])
left: CustomVariableDeclaration | CustomExpression right: CustomExpression body: CustomStatement isForEach: boolean loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom for
-in
statement node. The isForEach
flag indicates whether the node is a for each
statement.
breakStatement(label[, loc])
label: CustomIdentifier | null loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom break
statement node.
continueStatement(label[, loc])
label: CustomIdentifier | null loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom continue
statement node.
withStatement(obj, body[, loc])
obj: CustomExpression body: CustomStatement loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom with
statement node.
returnStatement(arg[, loc])
arg: CustomExpression | null loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom return
statement node.
tryStatement(body, handlers, fin[, loc])
body: CustomStatement handlers: [ CustomCatchClause ] fin: CustomStatement | null loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom try
statement node.
throwStatement(arg[, loc])
arg: CustomExpression loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom throw
statement node.
debuggerStatement([loc])
loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom debugger
statement node.
letStatement(head, body[, loc])
head: [ CustomDeclarator ] body: CustomStatement loc: SourceLocation
Returns: CustomStatement
Callback to produce a custom let
statement node.
Declarations
functionDeclaration(name, args, body, isGenerator, isExpression[, loc])
name: string args: [ CustomPattern ] body: CustomStatement | CustomExpression isGenerator: boolean isExpression: boolean loc: SourceLocation
Returns: CustomDeclaration
Callback to produce a custom function declaration node.
variableDeclaration(kind, dtors[, loc])
kind: "const" | "let" | "var" dtors: [ CustomDeclarator ] loc: SourceLocation
Returns: CustomDeclaration
Callback to produce a custom variable declaration node.
variableDeclarator(patt, init[, loc])
patt: CustomPattern init: CustomExpression | null loc: SourceLocation
Returns: CustomDeclarator
Callback to produce a custom variable declarator node.
Expressions
sequenceExpression(exprs[, loc])
exprs: [ CustomExpression ] loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom sequence expression node.
conditionalExpression(test, cons, alt[, loc])
test: CustomExpression cons: CustomExpression alt: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom conditional expression node.
unaryExpression(op, arg, isPrefix[, loc])
op: UnaryOperator arg: CustomExpression isPrefix: boolean loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom unary expression node.
binaryExpression(op, left, right[, loc])
op: BinaryOperator left: CustomExpression right: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom binary expression node.
assignmentExpression(op, left, right[, loc])
op: AssignmentOperator left: CustomExpression right: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom assignment expression node.
logicalExpression(op, left, right[, loc])
op: LogicalOperator left: CustomExpression right: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom logical expression node.
updateExpression(op, arg, isPrefix[, loc])
op: UpdateOperator arg: CustomExpression isPrefix: boolean loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom update expression node.
newExpression(callee, args[, loc])
callee: CustomExpression args: [ CustomExpression ] loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom new
-expression node.
callExpression(callee, args[, loc])
callee: CustomExpression args: [ CustomExpression ] loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom function call node.
memberExpression(obj, prop, isComputed[, loc])
obj: CustomExpression prop: CustomIdentifier | CustomExpression isComputed: boolean loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom member expression node.
functionExpression(name, args, body, isGenerator, isExpression[, loc])
name: CustomIdentifier | null args: [ CustomPattern ] body: CustomStatement | CustomExpression isGenerator: boolean isExpression: boolean loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom function expression node.
arrayExpression(elts[, loc])
elts: [ CustomExpression | null ] loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom array expression node.
objectExpression(props[, loc])
props: [ CustomObjectProperty ] loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom object expression node.
thisExpression([loc])
loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom this
expression node.
graphExpression(index, expr[, loc])
index: uint32 >= 1 expr: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom graph
expression node.
graphIndexExpression(index[, loc])
index: uint32 >= 1 loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom graph index
expression node.
comprehensionExpression(body, blocks, filter[, loc])
body: CustomExpression blocks: [ CustomComprehensionBlock | CustomComprehensionIf ] filter: CustomExpression | null loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom comprehension
expression node.
generatorExpression(body, blocks, filter[, loc])
body: CustomExpression blocks: [ CustomComprehensionBlock | CustomComprehensionIf ] filter: CustomExpression | null loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom generator
expression node.
yieldExpression(arg[, loc])
arg: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom yield
expression node.
letExpression(head, body[, loc])
head: [ CustomDeclarator ] body: CustomExpression loc: SourceLocation
Returns: CustomExpression
Callback to produce a custom let
expression node.
Patterns
arrayPattern(elts[, loc])
elts: [ CustomPattern | null ] loc: SourceLocation
Returns: CustomPattern
Callback to produce a custom array destructuring pattern node.
objectPattern(props[, loc])
props: [ CustomPropertyPattern ] loc: SourceLocation
Returns: CustomPattern
Callback to produce a custom object destructuring pattern node.
propertyPattern(key, patt[, loc])
key: CustomLiteral | CustomIdentifier patt: CustomPattern loc: SourceLocation
Returns: CustomPropertyPattern
Callback to produce a custom object property destructuring pattern node.
Clauses
switchCase(test, cons[, loc])
test: CustomExpression | null cons: [ CustomStatement ] loc: SourceLocation
Returns: CustomSwitchCase
Callback to produce a custom case
or default
clause node. The test
argument is null
if and only if the node is a default
clause.
catchClause(arg, guard, body[, loc])
arg: CustomPattern guard: CustomExpression body: CustomStatement loc: SourceLocation
Returns: CustomCatchClause
Callback to produce a custom catch
clause node.
comprehensionBlock(left, right, isForEach[, loc])
left: CustomPattern right: CustomExpression isForEach: boolean loc: SourceLocation
Returns: CustomComprehensionBlock
Callback to produce a custom comprehension block node. The isForEach
flag indicates whether the node is a for each
block.
comprehensionIf(test[, loc])
test: CustomExpression loc: SourceLocation
Returns: CustomComprehensionIf
Callback to produce a custom comprehension if node.
Miscellaneous
identifier(name[, loc])
name: string loc: SourceLocation
Returns: CustomIdentifier/CustomPattern/CustomExpression
Callback to produce a custom identifier node.
literal(val[, loc])
val: string | boolean | null | number | RegExp loc: SourceLocation
Returns: CustomLiteral / CustomExpression
Callback to produce a custom literal node.
property(kind, key, val[, loc])
kind: "init" | "get" | "set" key: CustomLiteral | CustomIdentifier val: CustomExpression loc: SourceLocation
Returns: CustomObjectProperty
Callback to produce a custom object property initializer node.
E4X
Declarations
xmlDefaultDeclaration(ns[, loc])
loc: SourceLocation
Returns: CustomDeclaration
Callback to produce a custom XML default namespace declaration node.
Expressions
xmlAnyName([loc])
loc: SourceLocation
Returns: CustomXMLAnyName/CustomXML/CustomExpression
Callback to produce a custom XML node for the wildcard pseudo-identifier *
.
xmlAttributeSelector(expr[, loc])
expr: CustomExpression loc: SourceLocation
Returns: CustomXML/CustomExpression
Callback to produce a custom XML attribute selector node.
xmlFilterExpression(left, right[, loc])
left: CustomExpression right: CustomExpression loc: SourceLocation
Returns: CustomXML/CustomExpression
Callback to produce a custom XML filter expression node.
xmlQualifiedIdentifier(left, right, isComputed[, loc])
left: CustomIdentifier | CustomXMLAnyName right: CustomIdentifier | CustomExpression isComputed: boolean loc: SourceLocation
Returns: CustomXML/CustomExpression
Callback to produce a custom qualified identifier node.
xmlFunctionQualifiedIdentifier(right, isComputed[, loc])
right: CustomIdentifier | CustomExpression isComputed: boolean loc: SourceLocation
Returns: CustomXML/CustomExpression
Callback to produce a custom XML function
-qualified identifier node.
xmlElement(contents[, loc])
contents: [ CustomXML ] loc: SourceLocation
Returns: CustomXML/CustomExpression
Callback to produce a custom XML element node.
xmlList(contents[, loc])
contents: [ CustomXML ] loc: SourceLocation
Returns: CustomXML/CustomExpression
Callback to produce a custom XML list node.
XML
xmlEscape(expr[, loc])
expr: CustomExpression loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML escape node.
xmlText(text[, loc])
text: string loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML text node.
xmlStartTag(contents[, loc])
contents: [ CustomXML ] loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML start-tag node.
xmlEndTag(contents[, loc])
contents: [ CustomXML ] loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML end-tag node.
xmlPointTag(contents[, loc])
contents: [ CustomXML ] loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML point tag node.
xmlName(contents[, loc])
contents: string | [ CustomXML ] loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML name node.
xmlAttribute(value[, loc])
value: string loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML attribute node.
xmlCdata(contents[, loc])
contents: string loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML CDATA
node.
xmlComment(contents[, loc])
contents: string loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML comment node.
xmlProcessingInstruction(target, contents[, loc])
target: string contents: string | null loc: SourceLocation
Returns: CustomXML
Callback to produce a custom XML processing instruction node.