Godeps, vendor: convert dependency management to trash (#3198)

This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.

10 files changed, 3933 insertions, 0 deletions

diff --git a/vendor/github.com/robertkrimen/otto/parser/Makefile b/vendor/github.com/robertkrimen/otto/parser/Makefile
new file mode 100644
index 000000000..766fd4d0b
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/Makefile
@@ -0,0 +1,4 @@
+.PHONY: test
+
+test:
+	go test
diff --git a/vendor/github.com/robertkrimen/otto/parser/README.markdown b/vendor/github.com/robertkrimen/otto/parser/README.markdown
new file mode 100644
index 000000000..c3cae5b60
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/README.markdown
@@ -0,0 +1,190 @@
+# parser
+--
+    import "github.com/robertkrimen/otto/parser"
+
+Package parser implements a parser for JavaScript.
+
+    import (
+        "github.com/robertkrimen/otto/parser"
+    )
+
+Parse and return an AST
+
+    filename := "" // A filename is optional
+    src := `
+        // Sample xyzzy example
+        (function(){
+            if (3.14159 > 0) {
+                console.log("Hello, World.");
+                return;
+            }
+
+            var xyzzy = NaN;
+            console.log("Nothing happens.");
+            return xyzzy;
+        })();
+    `
+
+    // Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
+    program, err := parser.ParseFile(nil, filename, src, 0)
+
+
+### Warning
+
+The parser and AST interfaces are still works-in-progress (particularly where
+node types are concerned) and may change in the future.
+
+## Usage
+
+#### func  ParseFile
+
+```go
+func ParseFile(fileSet *file.FileSet, filename string, src interface{}, mode Mode) (*ast.Program, error)
+```
+ParseFile parses the source code of a single JavaScript/ECMAScript source file
+and returns the corresponding ast.Program node.
+
+If fileSet == nil, ParseFile parses source without a FileSet. If fileSet != nil,
+ParseFile first adds filename and src to fileSet.
+
+The filename argument is optional and is used for labelling errors, etc.
+
+src may be a string, a byte slice, a bytes.Buffer, or an io.Reader, but it MUST
+always be in UTF-8.
+
+    // Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
+    program, err := parser.ParseFile(nil, "", `if (abc > 1) {}`, 0)
+
+#### func  ParseFunction
+
+```go
+func ParseFunction(parameterList, body string) (*ast.FunctionLiteral, error)
+```
+ParseFunction parses a given parameter list and body as a function and returns
+the corresponding ast.FunctionLiteral node.
+
+The parameter list, if any, should be a comma-separated list of identifiers.
+
+#### func  ReadSource
+
+```go
+func ReadSource(filename string, src interface{}) ([]byte, error)
+```
+
+#### func  TransformRegExp
+
+```go
+func TransformRegExp(pattern string) (string, error)
+```
+TransformRegExp transforms a JavaScript pattern into a Go "regexp" pattern.
+
+re2 (Go) cannot do backtracking, so the presence of a lookahead (?=) (?!) or
+backreference (\1, \2, ...) will cause an error.
+
+re2 (Go) has a different definition for \s: [\t\n\f\r ]. The JavaScript
+definition, on the other hand, also includes \v, Unicode "Separator, Space",
+etc.
+
+If the pattern is invalid (not valid even in JavaScript), then this function
+returns the empty string and an error.
+
+If the pattern is valid, but incompatible (contains a lookahead or
+backreference), then this function returns the transformation (a non-empty
+string) AND an error.
+
+#### type Error
+
+```go
+type Error struct {
+	Position file.Position
+	Message  string
+}
+```
+
+An Error represents a parsing error. It includes the position where the error
+occurred and a message/description.
+
+#### func (Error) Error
+
+```go
+func (self Error) Error() string
+```
+
+#### type ErrorList
+
+```go
+type ErrorList []*Error
+```
+
+ErrorList is a list of *Errors.
+
+#### func (*ErrorList) Add
+
+```go
+func (self *ErrorList) Add(position file.Position, msg string)
+```
+Add adds an Error with given position and message to an ErrorList.
+
+#### func (ErrorList) Err
+
+```go
+func (self ErrorList) Err() error
+```
+Err returns an error equivalent to this ErrorList. If the list is empty, Err
+returns nil.
+
+#### func (ErrorList) Error
+
+```go
+func (self ErrorList) Error() string
+```
+Error implements the Error interface.
+
+#### func (ErrorList) Len
+
+```go
+func (self ErrorList) Len() int
+```
+
+#### func (ErrorList) Less
+
+```go
+func (self ErrorList) Less(i, j int) bool
+```
+
+#### func (*ErrorList) Reset
+
+```go
+func (self *ErrorList) Reset()
+```
+Reset resets an ErrorList to no errors.
+
+#### func (ErrorList) Sort
+
+```go
+func (self ErrorList) Sort()
+```
+
+#### func (ErrorList) Swap
+
+```go
+func (self ErrorList) Swap(i, j int)
+```
+
+#### type Mode
+
+```go
+type Mode uint
+```
+
+A Mode value is a set of flags (or 0). They control optional parser
+functionality.
+
+```go
+const (
+	IgnoreRegExpErrors Mode = 1 << iota // Ignore RegExp compatibility errors (allow backtracking)
+)
+```
+
+--
+**godocdown** http://github.com/robertkrimen/godocdown
diff --git a/vendor/github.com/robertkrimen/otto/parser/dbg.go b/vendor/github.com/robertkrimen/otto/parser/dbg.go
new file mode 100644
index 000000000..3c5f2f698
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/dbg.go
@@ -0,0 +1,9 @@
+// This file was AUTOMATICALLY GENERATED by dbg-import (smuggol) for github.com/robertkrimen/dbg
+
+package parser
+
+import (
+	Dbg "github.com/robertkrimen/otto/dbg"
+)
+
+var dbg, dbgf = Dbg.New()
diff --git a/vendor/github.com/robertkrimen/otto/parser/error.go b/vendor/github.com/robertkrimen/otto/parser/error.go
new file mode 100644
index 000000000..e0f74a5cf
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/error.go
@@ -0,0 +1,175 @@
+package parser
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/robertkrimen/otto/file"
+	"github.com/robertkrimen/otto/token"
+)
+
+const (
+	err_UnexpectedToken      = "Unexpected token %v"
+	err_UnexpectedEndOfInput = "Unexpected end of input"
+	err_UnexpectedEscape     = "Unexpected escape"
+)
+
+//    UnexpectedNumber:  'Unexpected number',
+//    UnexpectedString:  'Unexpected string',
+//    UnexpectedIdentifier:  'Unexpected identifier',
+//    UnexpectedReserved:  'Unexpected reserved word',
+//    NewlineAfterThrow:  'Illegal newline after throw',
+//    InvalidRegExp: 'Invalid regular expression',
+//    UnterminatedRegExp:  'Invalid regular expression: missing /',
+//    InvalidLHSInAssignment:  'Invalid left-hand side in assignment',
+//    InvalidLHSInForIn:  'Invalid left-hand side in for-in',
+//    MultipleDefaultsInSwitch: 'More than one default clause in switch statement',
+//    NoCatchOrFinally:  'Missing catch or finally after try',
+//    UnknownLabel: 'Undefined label \'%0\'',
+//    Redeclaration: '%0 \'%1\' has already been declared',
+//    IllegalContinue: 'Illegal continue statement',
+//    IllegalBreak: 'Illegal break statement',
+//    IllegalReturn: 'Illegal return statement',
+//    StrictModeWith:  'Strict mode code may not include a with statement',
+//    StrictCatchVariable:  'Catch variable may not be eval or arguments in strict mode',
+//    StrictVarName:  'Variable name may not be eval or arguments in strict mode',
+//    StrictParamName:  'Parameter name eval or arguments is not allowed in strict mode',
+//    StrictParamDupe: 'Strict mode function may not have duplicate parameter names',
+//    StrictFunctionName:  'Function name may not be eval or arguments in strict mode',
+//    StrictOctalLiteral:  'Octal literals are not allowed in strict mode.',
+//    StrictDelete:  'Delete of an unqualified identifier in strict mode.',
+//    StrictDuplicateProperty:  'Duplicate data property in object literal not allowed in strict mode',
+//    AccessorDataProperty:  'Object literal may not have data and accessor property with the same name',
+//    AccessorGetSet:  'Object literal may not have multiple get/set accessors with the same name',
+//    StrictLHSAssignment:  'Assignment to eval or arguments is not allowed in strict mode',
+//    StrictLHSPostfix:  'Postfix increment/decrement may not have eval or arguments operand in strict mode',
+//    StrictLHSPrefix:  'Prefix increment/decrement may not have eval or arguments operand in strict mode',
+//    StrictReservedWord:  'Use of future reserved word in strict mode'
+
+// A SyntaxError is a description of an ECMAScript syntax error.
+
+// An Error represents a parsing error. It includes the position where the error occurred and a message/description.
+type Error struct {
+	Position file.Position
+	Message  string
+}
+
+// FIXME Should this be "SyntaxError"?
+
+func (self Error) Error() string {
+	filename := self.Position.Filename
+	if filename == "" {
+		filename = "(anonymous)"
+	}
+	return fmt.Sprintf("%s: Line %d:%d %s",
+		filename,
+		self.Position.Line,
+		self.Position.Column,
+		self.Message,
+	)
+}
+
+func (self *_parser) error(place interface{}, msg string, msgValues ...interface{}) *Error {
+	idx := file.Idx(0)
+	switch place := place.(type) {
+	case int:
+		idx = self.idxOf(place)
+	case file.Idx:
+		if place == 0 {
+			idx = self.idxOf(self.chrOffset)
+		} else {
+			idx = place
+		}
+	default:
+		panic(fmt.Errorf("error(%T, ...)", place))
+	}
+
+	position := self.position(idx)
+	msg = fmt.Sprintf(msg, msgValues...)
+	self.errors.Add(position, msg)
+	return self.errors[len(self.errors)-1]
+}
+
+func (self *_parser) errorUnexpected(idx file.Idx, chr rune) error {
+	if chr == -1 {
+		return self.error(idx, err_UnexpectedEndOfInput)
+	}
+	return self.error(idx, err_UnexpectedToken, token.ILLEGAL)
+}
+
+func (self *_parser) errorUnexpectedToken(tkn token.Token) error {
+	switch tkn {
+	case token.EOF:
+		return self.error(file.Idx(0), err_UnexpectedEndOfInput)
+	}
+	value := tkn.String()
+	switch tkn {
+	case token.BOOLEAN, token.NULL:
+		value = self.literal
+	case token.IDENTIFIER:
+		return self.error(self.idx, "Unexpected identifier")
+	case token.KEYWORD:
+		// TODO Might be a future reserved word
+		return self.error(self.idx, "Unexpected reserved word")
+	case token.NUMBER:
+		return self.error(self.idx, "Unexpected number")
+	case token.STRING:
+		return self.error(self.idx, "Unexpected string")
+	}
+	return self.error(self.idx, err_UnexpectedToken, value)
+}
+
+// ErrorList is a list of *Errors.
+//
+type ErrorList []*Error
+
+// Add adds an Error with given position and message to an ErrorList.
+func (self *ErrorList) Add(position file.Position, msg string) {
+	*self = append(*self, &Error{position, msg})
+}
+
+// Reset resets an ErrorList to no errors.
+func (self *ErrorList) Reset() { *self = (*self)[0:0] }
+
+func (self ErrorList) Len() int      { return len(self) }
+func (self ErrorList) Swap(i, j int) { self[i], self[j] = self[j], self[i] }
+func (self ErrorList) Less(i, j int) bool {
+	x := &self[i].Position
+	y := &self[j].Position
+	if x.Filename < y.Filename {
+		return true
+	}
+	if x.Filename == y.Filename {
+		if x.Line < y.Line {
+			return true
+		}
+		if x.Line == y.Line {
+			return x.Column < y.Column
+		}
+	}
+	return false
+}
+
+func (self ErrorList) Sort() {
+	sort.Sort(self)
+}
+
+// Error implements the Error interface.
+func (self ErrorList) Error() string {
+	switch len(self) {
+	case 0:
+		return "no errors"
+	case 1:
+		return self[0].Error()
+	}
+	return fmt.Sprintf("%s (and %d more errors)", self[0].Error(), len(self)-1)
+}
+
+// Err returns an error equivalent to this ErrorList.
+// If the list is empty, Err returns nil.
+func (self ErrorList) Err() error {
+	if len(self) == 0 {
+		return nil
+	}
+	return self
+}
diff --git a/vendor/github.com/robertkrimen/otto/parser/expression.go b/vendor/github.com/robertkrimen/otto/parser/expression.go
new file mode 100644
index 000000000..63a169d40
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/expression.go
@@ -0,0 +1,1005 @@
+package parser
+
+import (
+	"regexp"
+
+	"github.com/robertkrimen/otto/ast"
+	"github.com/robertkrimen/otto/file"
+	"github.com/robertkrimen/otto/token"
+)
+
+func (self *_parser) parseIdentifier() *ast.Identifier {
+	literal := self.literal
+	idx := self.idx
+	if self.mode&StoreComments != 0 {
+		self.comments.MarkComments(ast.LEADING)
+	}
+	self.next()
+	exp := &ast.Identifier{
+		Name: literal,
+		Idx:  idx,
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(exp)
+	}
+
+	return exp
+}
+
+func (self *_parser) parsePrimaryExpression() ast.Expression {
+	literal := self.literal
+	idx := self.idx
+	switch self.token {
+	case token.IDENTIFIER:
+		self.next()
+		if len(literal) > 1 {
+			tkn, strict := token.IsKeyword(literal)
+			if tkn == token.KEYWORD {
+				if !strict {
+					self.error(idx, "Unexpected reserved word")
+				}
+			}
+		}
+		return &ast.Identifier{
+			Name: literal,
+			Idx:  idx,
+		}
+	case token.NULL:
+		self.next()
+		return &ast.NullLiteral{
+			Idx:     idx,
+			Literal: literal,
+		}
+	case token.BOOLEAN:
+		self.next()
+		value := false
+		switch literal {
+		case "true":
+			value = true
+		case "false":
+			value = false
+		default:
+			self.error(idx, "Illegal boolean literal")
+		}
+		return &ast.BooleanLiteral{
+			Idx:     idx,
+			Literal: literal,
+			Value:   value,
+		}
+	case token.STRING:
+		self.next()
+		value, err := parseStringLiteral(literal[1 : len(literal)-1])
+		if err != nil {
+			self.error(idx, err.Error())
+		}
+		return &ast.StringLiteral{
+			Idx:     idx,
+			Literal: literal,
+			Value:   value,
+		}
+	case token.NUMBER:
+		self.next()
+		value, err := parseNumberLiteral(literal)
+		if err != nil {
+			self.error(idx, err.Error())
+			value = 0
+		}
+		return &ast.NumberLiteral{
+			Idx:     idx,
+			Literal: literal,
+			Value:   value,
+		}
+	case token.SLASH, token.QUOTIENT_ASSIGN:
+		return self.parseRegExpLiteral()
+	case token.LEFT_BRACE:
+		return self.parseObjectLiteral()
+	case token.LEFT_BRACKET:
+		return self.parseArrayLiteral()
+	case token.LEFT_PARENTHESIS:
+		self.expect(token.LEFT_PARENTHESIS)
+		expression := self.parseExpression()
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.expect(token.RIGHT_PARENTHESIS)
+		return expression
+	case token.THIS:
+		self.next()
+		return &ast.ThisExpression{
+			Idx: idx,
+		}
+	case token.FUNCTION:
+		return self.parseFunction(false)
+	}
+
+	self.errorUnexpectedToken(self.token)
+	self.nextStatement()
+	return &ast.BadExpression{From: idx, To: self.idx}
+}
+
+func (self *_parser) parseRegExpLiteral() *ast.RegExpLiteral {
+
+	offset := self.chrOffset - 1 // Opening slash already gotten
+	if self.token == token.QUOTIENT_ASSIGN {
+		offset -= 1 // =
+	}
+	idx := self.idxOf(offset)
+
+	pattern, err := self.scanString(offset)
+	endOffset := self.chrOffset
+
+	self.next()
+	if err == nil {
+		pattern = pattern[1 : len(pattern)-1]
+	}
+
+	flags := ""
+	if self.token == token.IDENTIFIER { // gim
+
+		flags = self.literal
+		self.next()
+		endOffset = self.chrOffset - 1
+	}
+
+	var value string
+	// TODO 15.10
+	{
+		// Test during parsing that this is a valid regular expression
+		// Sorry, (?=) and (?!) are invalid (for now)
+		pattern, err := TransformRegExp(pattern)
+		if err != nil {
+			if pattern == "" || self.mode&IgnoreRegExpErrors == 0 {
+				self.error(idx, "Invalid regular expression: %s", err.Error())
+			}
+		} else {
+			_, err = regexp.Compile(pattern)
+			if err != nil {
+				// We should not get here, ParseRegExp should catch any errors
+				self.error(idx, "Invalid regular expression: %s", err.Error()[22:]) // Skip redundant "parse regexp error"
+			} else {
+				value = pattern
+			}
+		}
+	}
+
+	literal := self.str[offset:endOffset]
+
+	return &ast.RegExpLiteral{
+		Idx:     idx,
+		Literal: literal,
+		Pattern: pattern,
+		Flags:   flags,
+		Value:   value,
+	}
+}
+
+func (self *_parser) parseVariableDeclaration(declarationList *[]*ast.VariableExpression) ast.Expression {
+
+	if self.token != token.IDENTIFIER {
+		idx := self.expect(token.IDENTIFIER)
+		self.nextStatement()
+		return &ast.BadExpression{From: idx, To: self.idx}
+	}
+
+	literal := self.literal
+	idx := self.idx
+	self.next()
+	node := &ast.VariableExpression{
+		Name: literal,
+		Idx:  idx,
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(node)
+	}
+
+	if declarationList != nil {
+		*declarationList = append(*declarationList, node)
+	}
+
+	if self.token == token.ASSIGN {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+		node.Initializer = self.parseAssignmentExpression()
+	}
+
+	return node
+}
+
+func (self *_parser) parseVariableDeclarationList(var_ file.Idx) []ast.Expression {
+
+	var declarationList []*ast.VariableExpression // Avoid bad expressions
+	var list []ast.Expression
+
+	for {
+		if self.mode&StoreComments != 0 {
+			self.comments.MarkComments(ast.LEADING)
+		}
+		decl := self.parseVariableDeclaration(&declarationList)
+		list = append(list, decl)
+		if self.token != token.COMMA {
+			break
+		}
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+	}
+
+	self.scope.declare(&ast.VariableDeclaration{
+		Var:  var_,
+		List: declarationList,
+	})
+
+	return list
+}
+
+func (self *_parser) parseObjectPropertyKey() (string, string) {
+	idx, tkn, literal := self.idx, self.token, self.literal
+	value := ""
+	if self.mode&StoreComments != 0 {
+		self.comments.MarkComments(ast.KEY)
+	}
+	self.next()
+
+	switch tkn {
+	case token.IDENTIFIER:
+		value = literal
+	case token.NUMBER:
+		var err error
+		_, err = parseNumberLiteral(literal)
+		if err != nil {
+			self.error(idx, err.Error())
+		} else {
+			value = literal
+		}
+	case token.STRING:
+		var err error
+		value, err = parseStringLiteral(literal[1 : len(literal)-1])
+		if err != nil {
+			self.error(idx, err.Error())
+		}
+	default:
+		// null, false, class, etc.
+		if matchIdentifier.MatchString(literal) {
+			value = literal
+		}
+	}
+	return literal, value
+}
+
+func (self *_parser) parseObjectProperty() ast.Property {
+	literal, value := self.parseObjectPropertyKey()
+	if literal == "get" && self.token != token.COLON {
+		idx := self.idx
+		_, value := self.parseObjectPropertyKey()
+		parameterList := self.parseFunctionParameterList()
+
+		node := &ast.FunctionLiteral{
+			Function:      idx,
+			ParameterList: parameterList,
+		}
+		self.parseFunctionBlock(node)
+		return ast.Property{
+			Key:   value,
+			Kind:  "get",
+			Value: node,
+		}
+	} else if literal == "set" && self.token != token.COLON {
+		idx := self.idx
+		_, value := self.parseObjectPropertyKey()
+		parameterList := self.parseFunctionParameterList()
+
+		node := &ast.FunctionLiteral{
+			Function:      idx,
+			ParameterList: parameterList,
+		}
+		self.parseFunctionBlock(node)
+		return ast.Property{
+			Key:   value,
+			Kind:  "set",
+			Value: node,
+		}
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.MarkComments(ast.COLON)
+	}
+	self.expect(token.COLON)
+
+	exp := ast.Property{
+		Key:   value,
+		Kind:  "value",
+		Value: self.parseAssignmentExpression(),
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(exp.Value)
+	}
+	return exp
+}
+
+func (self *_parser) parseObjectLiteral() ast.Expression {
+	var value []ast.Property
+	idx0 := self.expect(token.LEFT_BRACE)
+	for self.token != token.RIGHT_BRACE && self.token != token.EOF {
+		value = append(value, self.parseObjectProperty())
+		if self.token == token.COMMA {
+			if self.mode&StoreComments != 0 {
+				self.comments.Unset()
+			}
+			self.next()
+			continue
+		}
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.MarkComments(ast.FINAL)
+	}
+	idx1 := self.expect(token.RIGHT_BRACE)
+
+	return &ast.ObjectLiteral{
+		LeftBrace:  idx0,
+		RightBrace: idx1,
+		Value:      value,
+	}
+}
+
+func (self *_parser) parseArrayLiteral() ast.Expression {
+	idx0 := self.expect(token.LEFT_BRACKET)
+	var value []ast.Expression
+	for self.token != token.RIGHT_BRACKET && self.token != token.EOF {
+		if self.token == token.COMMA {
+			// This kind of comment requires a special empty expression node.
+			empty := &ast.EmptyExpression{self.idx, self.idx}
+
+			if self.mode&StoreComments != 0 {
+				self.comments.SetExpression(empty)
+				self.comments.Unset()
+			}
+			value = append(value, empty)
+			self.next()
+			continue
+		}
+
+		exp := self.parseAssignmentExpression()
+
+		value = append(value, exp)
+		if self.token != token.RIGHT_BRACKET {
+			if self.mode&StoreComments != 0 {
+				self.comments.Unset()
+			}
+			self.expect(token.COMMA)
+		}
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.MarkComments(ast.FINAL)
+	}
+	idx1 := self.expect(token.RIGHT_BRACKET)
+
+	return &ast.ArrayLiteral{
+		LeftBracket:  idx0,
+		RightBracket: idx1,
+		Value:        value,
+	}
+}
+
+func (self *_parser) parseArgumentList() (argumentList []ast.Expression, idx0, idx1 file.Idx) {
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	idx0 = self.expect(token.LEFT_PARENTHESIS)
+	if self.token != token.RIGHT_PARENTHESIS {
+		for {
+			exp := self.parseAssignmentExpression()
+			if self.mode&StoreComments != 0 {
+				self.comments.SetExpression(exp)
+			}
+			argumentList = append(argumentList, exp)
+			if self.token != token.COMMA {
+				break
+			}
+			if self.mode&StoreComments != 0 {
+				self.comments.Unset()
+			}
+			self.next()
+		}
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	idx1 = self.expect(token.RIGHT_PARENTHESIS)
+	return
+}
+
+func (self *_parser) parseCallExpression(left ast.Expression) ast.Expression {
+	argumentList, idx0, idx1 := self.parseArgumentList()
+	exp := &ast.CallExpression{
+		Callee:           left,
+		LeftParenthesis:  idx0,
+		ArgumentList:     argumentList,
+		RightParenthesis: idx1,
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(exp)
+	}
+	return exp
+}
+
+func (self *_parser) parseDotMember(left ast.Expression) ast.Expression {
+	period := self.expect(token.PERIOD)
+
+	literal := self.literal
+	idx := self.idx
+
+	if !matchIdentifier.MatchString(literal) {
+		self.expect(token.IDENTIFIER)
+		self.nextStatement()
+		return &ast.BadExpression{From: period, To: self.idx}
+	}
+
+	self.next()
+
+	return &ast.DotExpression{
+		Left: left,
+		Identifier: &ast.Identifier{
+			Idx:  idx,
+			Name: literal,
+		},
+	}
+}
+
+func (self *_parser) parseBracketMember(left ast.Expression) ast.Expression {
+	idx0 := self.expect(token.LEFT_BRACKET)
+	member := self.parseExpression()
+	idx1 := self.expect(token.RIGHT_BRACKET)
+	return &ast.BracketExpression{
+		LeftBracket:  idx0,
+		Left:         left,
+		Member:       member,
+		RightBracket: idx1,
+	}
+}
+
+func (self *_parser) parseNewExpression() ast.Expression {
+	idx := self.expect(token.NEW)
+	callee := self.parseLeftHandSideExpression()
+	node := &ast.NewExpression{
+		New:    idx,
+		Callee: callee,
+	}
+	if self.token == token.LEFT_PARENTHESIS {
+		argumentList, idx0, idx1 := self.parseArgumentList()
+		node.ArgumentList = argumentList
+		node.LeftParenthesis = idx0
+		node.RightParenthesis = idx1
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(node)
+	}
+
+	return node
+}
+
+func (self *_parser) parseLeftHandSideExpression() ast.Expression {
+
+	var left ast.Expression
+	if self.token == token.NEW {
+		left = self.parseNewExpression()
+	} else {
+		if self.mode&StoreComments != 0 {
+			self.comments.MarkComments(ast.LEADING)
+			self.comments.MarkPrimary()
+		}
+		left = self.parsePrimaryExpression()
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(left)
+	}
+
+	for {
+		if self.token == token.PERIOD {
+			left = self.parseDotMember(left)
+		} else if self.token == token.LEFT_BRACKET {
+			left = self.parseBracketMember(left)
+		} else {
+			break
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseLeftHandSideExpressionAllowCall() ast.Expression {
+
+	allowIn := self.scope.allowIn
+	self.scope.allowIn = true
+	defer func() {
+		self.scope.allowIn = allowIn
+	}()
+
+	var left ast.Expression
+	if self.token == token.NEW {
+		var newComments []*ast.Comment
+		if self.mode&StoreComments != 0 {
+			newComments = self.comments.FetchAll()
+			self.comments.MarkComments(ast.LEADING)
+			self.comments.MarkPrimary()
+		}
+		left = self.parseNewExpression()
+		if self.mode&StoreComments != 0 {
+			self.comments.CommentMap.AddComments(left, newComments, ast.LEADING)
+		}
+	} else {
+		if self.mode&StoreComments != 0 {
+			self.comments.MarkComments(ast.LEADING)
+			self.comments.MarkPrimary()
+		}
+		left = self.parsePrimaryExpression()
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.SetExpression(left)
+	}
+
+	for {
+		if self.token == token.PERIOD {
+			left = self.parseDotMember(left)
+		} else if self.token == token.LEFT_BRACKET {
+			left = self.parseBracketMember(left)
+		} else if self.token == token.LEFT_PARENTHESIS {
+			left = self.parseCallExpression(left)
+		} else {
+			break
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parsePostfixExpression() ast.Expression {
+	operand := self.parseLeftHandSideExpressionAllowCall()
+
+	switch self.token {
+	case token.INCREMENT, token.DECREMENT:
+		// Make sure there is no line terminator here
+		if self.implicitSemicolon {
+			break
+		}
+		tkn := self.token
+		idx := self.idx
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+		switch operand.(type) {
+		case *ast.Identifier, *ast.DotExpression, *ast.BracketExpression:
+		default:
+			self.error(idx, "Invalid left-hand side in assignment")
+			self.nextStatement()
+			return &ast.BadExpression{From: idx, To: self.idx}
+		}
+		exp := &ast.UnaryExpression{
+			Operator: tkn,
+			Idx:      idx,
+			Operand:  operand,
+			Postfix:  true,
+		}
+
+		if self.mode&StoreComments != 0 {
+			self.comments.SetExpression(exp)
+		}
+
+		return exp
+	}
+
+	return operand
+}
+
+func (self *_parser) parseUnaryExpression() ast.Expression {
+
+	switch self.token {
+	case token.PLUS, token.MINUS, token.NOT, token.BITWISE_NOT:
+		fallthrough
+	case token.DELETE, token.VOID, token.TYPEOF:
+		tkn := self.token
+		idx := self.idx
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		return &ast.UnaryExpression{
+			Operator: tkn,
+			Idx:      idx,
+			Operand:  self.parseUnaryExpression(),
+		}
+	case token.INCREMENT, token.DECREMENT:
+		tkn := self.token
+		idx := self.idx
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+		operand := self.parseUnaryExpression()
+		switch operand.(type) {
+		case *ast.Identifier, *ast.DotExpression, *ast.BracketExpression:
+		default:
+			self.error(idx, "Invalid left-hand side in assignment")
+			self.nextStatement()
+			return &ast.BadExpression{From: idx, To: self.idx}
+		}
+		return &ast.UnaryExpression{
+			Operator: tkn,
+			Idx:      idx,
+			Operand:  operand,
+		}
+	}
+
+	return self.parsePostfixExpression()
+}
+
+func (self *_parser) parseMultiplicativeExpression() ast.Expression {
+	next := self.parseUnaryExpression
+	left := next()
+
+	for self.token == token.MULTIPLY || self.token == token.SLASH ||
+		self.token == token.REMAINDER {
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseAdditiveExpression() ast.Expression {
+	next := self.parseMultiplicativeExpression
+	left := next()
+
+	for self.token == token.PLUS || self.token == token.MINUS {
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseShiftExpression() ast.Expression {
+	next := self.parseAdditiveExpression
+	left := next()
+
+	for self.token == token.SHIFT_LEFT || self.token == token.SHIFT_RIGHT ||
+		self.token == token.UNSIGNED_SHIFT_RIGHT {
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseRelationalExpression() ast.Expression {
+	next := self.parseShiftExpression
+	left := next()
+
+	allowIn := self.scope.allowIn
+	self.scope.allowIn = true
+	defer func() {
+		self.scope.allowIn = allowIn
+	}()
+
+	switch self.token {
+	case token.LESS, token.LESS_OR_EQUAL, token.GREATER, token.GREATER_OR_EQUAL:
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		exp := &ast.BinaryExpression{
+			Operator:   tkn,
+			Left:       left,
+			Right:      self.parseRelationalExpression(),
+			Comparison: true,
+		}
+		return exp
+	case token.INSTANCEOF:
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		exp := &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    self.parseRelationalExpression(),
+		}
+		return exp
+	case token.IN:
+		if !allowIn {
+			return left
+		}
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		exp := &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    self.parseRelationalExpression(),
+		}
+		return exp
+	}
+
+	return left
+}
+
+func (self *_parser) parseEqualityExpression() ast.Expression {
+	next := self.parseRelationalExpression
+	left := next()
+
+	for self.token == token.EQUAL || self.token == token.NOT_EQUAL ||
+		self.token == token.STRICT_EQUAL || self.token == token.STRICT_NOT_EQUAL {
+		tkn := self.token
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator:   tkn,
+			Left:       left,
+			Right:      next(),
+			Comparison: true,
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseBitwiseAndExpression() ast.Expression {
+	next := self.parseEqualityExpression
+	left := next()
+
+	for self.token == token.AND {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		tkn := self.token
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseBitwiseExclusiveOrExpression() ast.Expression {
+	next := self.parseBitwiseAndExpression
+	left := next()
+
+	for self.token == token.EXCLUSIVE_OR {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		tkn := self.token
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseBitwiseOrExpression() ast.Expression {
+	next := self.parseBitwiseExclusiveOrExpression
+	left := next()
+
+	for self.token == token.OR {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		tkn := self.token
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseLogicalAndExpression() ast.Expression {
+	next := self.parseBitwiseOrExpression
+	left := next()
+
+	for self.token == token.LOGICAL_AND {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		tkn := self.token
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseLogicalOrExpression() ast.Expression {
+	next := self.parseLogicalAndExpression
+	left := next()
+
+	for self.token == token.LOGICAL_OR {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		tkn := self.token
+		self.next()
+
+		left = &ast.BinaryExpression{
+			Operator: tkn,
+			Left:     left,
+			Right:    next(),
+		}
+	}
+
+	return left
+}
+
+func (self *_parser) parseConditionlExpression() ast.Expression {
+	left := self.parseLogicalOrExpression()
+
+	if self.token == token.QUESTION_MARK {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+
+		consequent := self.parseAssignmentExpression()
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.expect(token.COLON)
+		exp := &ast.ConditionalExpression{
+			Test:       left,
+			Consequent: consequent,
+			Alternate:  self.parseAssignmentExpression(),
+		}
+
+		return exp
+	}
+
+	return left
+}
+
+func (self *_parser) parseAssignmentExpression() ast.Expression {
+	left := self.parseConditionlExpression()
+	var operator token.Token
+	switch self.token {
+	case token.ASSIGN:
+		operator = self.token
+	case token.ADD_ASSIGN:
+		operator = token.PLUS
+	case token.SUBTRACT_ASSIGN:
+		operator = token.MINUS
+	case token.MULTIPLY_ASSIGN:
+		operator = token.MULTIPLY
+	case token.QUOTIENT_ASSIGN:
+		operator = token.SLASH
+	case token.REMAINDER_ASSIGN:
+		operator = token.REMAINDER
+	case token.AND_ASSIGN:
+		operator = token.AND
+	case token.AND_NOT_ASSIGN:
+		operator = token.AND_NOT
+	case token.OR_ASSIGN:
+		operator = token.OR
+	case token.EXCLUSIVE_OR_ASSIGN:
+		operator = token.EXCLUSIVE_OR
+	case token.SHIFT_LEFT_ASSIGN:
+		operator = token.SHIFT_LEFT
+	case token.SHIFT_RIGHT_ASSIGN:
+		operator = token.SHIFT_RIGHT
+	case token.UNSIGNED_SHIFT_RIGHT_ASSIGN:
+		operator = token.UNSIGNED_SHIFT_RIGHT
+	}
+
+	if operator != 0 {
+		idx := self.idx
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+		switch left.(type) {
+		case *ast.Identifier, *ast.DotExpression, *ast.BracketExpression:
+		default:
+			self.error(left.Idx0(), "Invalid left-hand side in assignment")
+			self.nextStatement()
+			return &ast.BadExpression{From: idx, To: self.idx}
+		}
+
+		exp := &ast.AssignExpression{
+			Left:     left,
+			Operator: operator,
+			Right:    self.parseAssignmentExpression(),
+		}
+
+		if self.mode&StoreComments != 0 {
+			self.comments.SetExpression(exp)
+		}
+
+		return exp
+	}
+
+	return left
+}
+
+func (self *_parser) parseExpression() ast.Expression {
+	next := self.parseAssignmentExpression
+	left := next()
+
+	if self.token == token.COMMA {
+		sequence := []ast.Expression{left}
+		for {
+			if self.token != token.COMMA {
+				break
+			}
+			self.next()
+			sequence = append(sequence, next())
+		}
+		return &ast.SequenceExpression{
+			Sequence: sequence,
+		}
+	}
+
+	return left
+}
diff --git a/vendor/github.com/robertkrimen/otto/parser/lexer.go b/vendor/github.com/robertkrimen/otto/parser/lexer.go
new file mode 100644
index 000000000..d9d69e124
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/lexer.go
@@ -0,0 +1,866 @@
+package parser
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+
+	"github.com/robertkrimen/otto/ast"
+	"github.com/robertkrimen/otto/file"
+	"github.com/robertkrimen/otto/token"
+)
+
+type _chr struct {
+	value rune
+	width int
+}
+
+var matchIdentifier = regexp.MustCompile(`^[$_\p{L}][$_\p{L}\d}]*$`)
+
+func isDecimalDigit(chr rune) bool {
+	return '0' <= chr && chr <= '9'
+}
+
+func digitValue(chr rune) int {
+	switch {
+	case '0' <= chr && chr <= '9':
+		return int(chr - '0')
+	case 'a' <= chr && chr <= 'f':
+		return int(chr - 'a' + 10)
+	case 'A' <= chr && chr <= 'F':
+		return int(chr - 'A' + 10)
+	}
+	return 16 // Larger than any legal digit value
+}
+
+func isDigit(chr rune, base int) bool {
+	return digitValue(chr) < base
+}
+
+func isIdentifierStart(chr rune) bool {
+	return chr == '$' || chr == '_' || chr == '\\' ||
+		'a' <= chr && chr <= 'z' || 'A' <= chr && chr <= 'Z' ||
+		chr >= utf8.RuneSelf && unicode.IsLetter(chr)
+}
+
+func isIdentifierPart(chr rune) bool {
+	return chr == '$' || chr == '_' || chr == '\\' ||
+		'a' <= chr && chr <= 'z' || 'A' <= chr && chr <= 'Z' ||
+		'0' <= chr && chr <= '9' ||
+		chr >= utf8.RuneSelf && (unicode.IsLetter(chr) || unicode.IsDigit(chr))
+}
+
+func (self *_parser) scanIdentifier() (string, error) {
+	offset := self.chrOffset
+	parse := false
+	for isIdentifierPart(self.chr) {
+		if self.chr == '\\' {
+			distance := self.chrOffset - offset
+			self.read()
+			if self.chr != 'u' {
+				return "", fmt.Errorf("Invalid identifier escape character: %c (%s)", self.chr, string(self.chr))
+			}
+			parse = true
+			var value rune
+			for j := 0; j < 4; j++ {
+				self.read()
+				decimal, ok := hex2decimal(byte(self.chr))
+				if !ok {
+					return "", fmt.Errorf("Invalid identifier escape character: %c (%s)", self.chr, string(self.chr))
+				}
+				value = value<<4 | decimal
+			}
+			if value == '\\' {
+				return "", fmt.Errorf("Invalid identifier escape value: %c (%s)", value, string(value))
+			} else if distance == 0 {
+				if !isIdentifierStart(value) {
+					return "", fmt.Errorf("Invalid identifier escape value: %c (%s)", value, string(value))
+				}
+			} else if distance > 0 {
+				if !isIdentifierPart(value) {
+					return "", fmt.Errorf("Invalid identifier escape value: %c (%s)", value, string(value))
+				}
+			}
+		}
+		self.read()
+	}
+	literal := string(self.str[offset:self.chrOffset])
+	if parse {
+		return parseStringLiteral(literal)
+	}
+	return literal, nil
+}
+
+// 7.2
+func isLineWhiteSpace(chr rune) bool {
+	switch chr {
+	case '\u0009', '\u000b', '\u000c', '\u0020', '\u00a0', '\ufeff':
+		return true
+	case '\u000a', '\u000d', '\u2028', '\u2029':
+		return false
+	case '\u0085':
+		return false
+	}
+	return unicode.IsSpace(chr)
+}
+
+// 7.3
+func isLineTerminator(chr rune) bool {
+	switch chr {
+	case '\u000a', '\u000d', '\u2028', '\u2029':
+		return true
+	}
+	return false
+}
+
+func (self *_parser) scan() (tkn token.Token, literal string, idx file.Idx) {
+
+	self.implicitSemicolon = false
+
+	for {
+		self.skipWhiteSpace()
+
+		idx = self.idxOf(self.chrOffset)
+		insertSemicolon := false
+
+		switch chr := self.chr; {
+		case isIdentifierStart(chr):
+			var err error
+			literal, err = self.scanIdentifier()
+			if err != nil {
+				tkn = token.ILLEGAL
+				break
+			}
+			if len(literal) > 1 {
+				// Keywords are longer than 1 character, avoid lookup otherwise
+				var strict bool
+				tkn, strict = token.IsKeyword(literal)
+
+				switch tkn {
+
+				case 0: // Not a keyword
+					if literal == "true" || literal == "false" {
+						self.insertSemicolon = true
+						tkn = token.BOOLEAN
+						return
+					} else if literal == "null" {
+						self.insertSemicolon = true
+						tkn = token.NULL
+						return
+					}
+
+				case token.KEYWORD:
+					tkn = token.KEYWORD
+					if strict {
+						// TODO If strict and in strict mode, then this is not a break
+						break
+					}
+					return
+
+				case
+					token.THIS,
+					token.BREAK,
+					token.THROW, // A newline after a throw is not allowed, but we need to detect it
+					token.RETURN,
+					token.CONTINUE,
+					token.DEBUGGER:
+					self.insertSemicolon = true
+					return
+
+				default:
+					return
+
+				}
+			}
+			self.insertSemicolon = true
+			tkn = token.IDENTIFIER
+			return
+		case '0' <= chr && chr <= '9':
+			self.insertSemicolon = true
+			tkn, literal = self.scanNumericLiteral(false)
+			return
+		default:
+			self.read()
+			switch chr {
+			case -1:
+				if self.insertSemicolon {
+					self.insertSemicolon = false
+					self.implicitSemicolon = true
+				}
+				tkn = token.EOF
+			case '\r', '\n', '\u2028', '\u2029':
+				self.insertSemicolon = false
+				self.implicitSemicolon = true
+				self.comments.AtLineBreak()
+				continue
+			case ':':
+				tkn = token.COLON
+			case '.':
+				if digitValue(self.chr) < 10 {
+					insertSemicolon = true
+					tkn, literal = self.scanNumericLiteral(true)
+				} else {
+					tkn = token.PERIOD
+				}
+			case ',':
+				tkn = token.COMMA
+			case ';':
+				tkn = token.SEMICOLON
+			case '(':
+				tkn = token.LEFT_PARENTHESIS
+			case ')':
+				tkn = token.RIGHT_PARENTHESIS
+				insertSemicolon = true
+			case '[':
+				tkn = token.LEFT_BRACKET
+			case ']':
+				tkn = token.RIGHT_BRACKET
+				insertSemicolon = true
+			case '{':
+				tkn = token.LEFT_BRACE
+			case '}':
+				tkn = token.RIGHT_BRACE
+				insertSemicolon = true
+			case '+':
+				tkn = self.switch3(token.PLUS, token.ADD_ASSIGN, '+', token.INCREMENT)
+				if tkn == token.INCREMENT {
+					insertSemicolon = true
+				}
+			case '-':
+				tkn = self.switch3(token.MINUS, token.SUBTRACT_ASSIGN, '-', token.DECREMENT)
+				if tkn == token.DECREMENT {
+					insertSemicolon = true
+				}
+			case '*':
+				tkn = self.switch2(token.MULTIPLY, token.MULTIPLY_ASSIGN)
+			case '/':
+				if self.chr == '/' {
+					if self.mode&StoreComments != 0 {
+						literal := string(self.readSingleLineComment())
+						self.comments.AddComment(ast.NewComment(literal, self.idx))
+						continue
+					}
+					self.skipSingleLineComment()
+					continue
+				} else if self.chr == '*' {
+					if self.mode&StoreComments != 0 {
+						literal = string(self.readMultiLineComment())
+						self.comments.AddComment(ast.NewComment(literal, self.idx))
+						continue
+					}
+					self.skipMultiLineComment()
+					continue
+				} else {
+					// Could be division, could be RegExp literal
+					tkn = self.switch2(token.SLASH, token.QUOTIENT_ASSIGN)
+					insertSemicolon = true
+				}
+			case '%':
+				tkn = self.switch2(token.REMAINDER, token.REMAINDER_ASSIGN)
+			case '^':
+				tkn = self.switch2(token.EXCLUSIVE_OR, token.EXCLUSIVE_OR_ASSIGN)
+			case '<':
+				tkn = self.switch4(token.LESS, token.LESS_OR_EQUAL, '<', token.SHIFT_LEFT, token.SHIFT_LEFT_ASSIGN)
+			case '>':
+				tkn = self.switch6(token.GREATER, token.GREATER_OR_EQUAL, '>', token.SHIFT_RIGHT, token.SHIFT_RIGHT_ASSIGN, '>', token.UNSIGNED_SHIFT_RIGHT, token.UNSIGNED_SHIFT_RIGHT_ASSIGN)
+			case '=':
+				tkn = self.switch2(token.ASSIGN, token.EQUAL)
+				if tkn == token.EQUAL && self.chr == '=' {
+					self.read()
+					tkn = token.STRICT_EQUAL
+				}
+			case '!':
+				tkn = self.switch2(token.NOT, token.NOT_EQUAL)
+				if tkn == token.NOT_EQUAL && self.chr == '=' {
+					self.read()
+					tkn = token.STRICT_NOT_EQUAL
+				}
+			case '&':
+				if self.chr == '^' {
+					self.read()
+					tkn = self.switch2(token.AND_NOT, token.AND_NOT_ASSIGN)
+				} else {
+					tkn = self.switch3(token.AND, token.AND_ASSIGN, '&', token.LOGICAL_AND)
+				}
+			case '|':
+				tkn = self.switch3(token.OR, token.OR_ASSIGN, '|', token.LOGICAL_OR)
+			case '~':
+				tkn = token.BITWISE_NOT
+			case '?':
+				tkn = token.QUESTION_MARK
+			case '"', '\'':
+				insertSemicolon = true
+				tkn = token.STRING
+				var err error
+				literal, err = self.scanString(self.chrOffset - 1)
+				if err != nil {
+					tkn = token.ILLEGAL
+				}
+			default:
+				self.errorUnexpected(idx, chr)
+				tkn = token.ILLEGAL
+			}
+		}
+		self.insertSemicolon = insertSemicolon
+		return
+	}
+}
+
+func (self *_parser) switch2(tkn0, tkn1 token.Token) token.Token {
+	if self.chr == '=' {
+		self.read()
+		return tkn1
+	}
+	return tkn0
+}
+
+func (self *_parser) switch3(tkn0, tkn1 token.Token, chr2 rune, tkn2 token.Token) token.Token {
+	if self.chr == '=' {
+		self.read()
+		return tkn1
+	}
+	if self.chr == chr2 {
+		self.read()
+		return tkn2
+	}
+	return tkn0
+}
+
+func (self *_parser) switch4(tkn0, tkn1 token.Token, chr2 rune, tkn2, tkn3 token.Token) token.Token {
+	if self.chr == '=' {
+		self.read()
+		return tkn1
+	}
+	if self.chr == chr2 {
+		self.read()
+		if self.chr == '=' {
+			self.read()
+			return tkn3
+		}
+		return tkn2
+	}
+	return tkn0
+}
+
+func (self *_parser) switch6(tkn0, tkn1 token.Token, chr2 rune, tkn2, tkn3 token.Token, chr3 rune, tkn4, tkn5 token.Token) token.Token {
+	if self.chr == '=' {
+		self.read()
+		return tkn1
+	}
+	if self.chr == chr2 {
+		self.read()
+		if self.chr == '=' {
+			self.read()
+			return tkn3
+		}
+		if self.chr == chr3 {
+			self.read()
+			if self.chr == '=' {
+				self.read()
+				return tkn5
+			}
+			return tkn4
+		}
+		return tkn2
+	}
+	return tkn0
+}
+
+func (self *_parser) chrAt(index int) _chr {
+	value, width := utf8.DecodeRuneInString(self.str[index:])
+	return _chr{
+		value: value,
+		width: width,
+	}
+}
+
+func (self *_parser) _peek() rune {
+	if self.offset+1 < self.length {
+		return rune(self.str[self.offset+1])
+	}
+	return -1
+}
+
+func (self *_parser) read() {
+	if self.offset < self.length {
+		self.chrOffset = self.offset
+		chr, width := rune(self.str[self.offset]), 1
+		if chr >= utf8.RuneSelf { // !ASCII
+			chr, width = utf8.DecodeRuneInString(self.str[self.offset:])
+			if chr == utf8.RuneError && width == 1 {
+				self.error(self.chrOffset, "Invalid UTF-8 character")
+			}
+		}
+		self.offset += width
+		self.chr = chr
+	} else {
+		self.chrOffset = self.length
+		self.chr = -1 // EOF
+	}
+}
+
+// This is here since the functions are so similar
+func (self *_RegExp_parser) read() {
+	if self.offset < self.length {
+		self.chrOffset = self.offset
+		chr, width := rune(self.str[self.offset]), 1
+		if chr >= utf8.RuneSelf { // !ASCII
+			chr, width = utf8.DecodeRuneInString(self.str[self.offset:])
+			if chr == utf8.RuneError && width == 1 {
+				self.error(self.chrOffset, "Invalid UTF-8 character")
+			}
+		}
+		self.offset += width
+		self.chr = chr
+	} else {
+		self.chrOffset = self.length
+		self.chr = -1 // EOF
+	}
+}
+
+func (self *_parser) readSingleLineComment() (result []rune) {
+	for self.chr != -1 {
+		self.read()
+		if isLineTerminator(self.chr) {
+			return
+		}
+		result = append(result, self.chr)
+	}
+
+	// Get rid of the trailing -1
+	result = result[:len(result)-1]
+
+	return
+}
+
+func (self *_parser) readMultiLineComment() (result []rune) {
+	self.read()
+	for self.chr >= 0 {
+		chr := self.chr
+		self.read()
+		if chr == '*' && self.chr == '/' {
+			self.read()
+			return
+		}
+
+		result = append(result, chr)
+	}
+
+	self.errorUnexpected(0, self.chr)
+
+	return
+}
+
+func (self *_parser) skipSingleLineComment() {
+	for self.chr != -1 {
+		self.read()
+		if isLineTerminator(self.chr) {
+			return
+		}
+	}
+}
+
+func (self *_parser) skipMultiLineComment() {
+	self.read()
+	for self.chr >= 0 {
+		chr := self.chr
+		self.read()
+		if chr == '*' && self.chr == '/' {
+			self.read()
+			return
+		}
+	}
+
+	self.errorUnexpected(0, self.chr)
+}
+
+func (self *_parser) skipWhiteSpace() {
+	for {
+		switch self.chr {
+		case ' ', '\t', '\f', '\v', '\u00a0', '\ufeff':
+			self.read()
+			continue
+		case '\r':
+			if self._peek() == '\n' {
+				self.comments.AtLineBreak()
+				self.read()
+			}
+			fallthrough
+		case '\u2028', '\u2029', '\n':
+			if self.insertSemicolon {
+				return
+			}
+			self.comments.AtLineBreak()
+			self.read()
+			continue
+		}
+		if self.chr >= utf8.RuneSelf {
+			if unicode.IsSpace(self.chr) {
+				self.read()
+				continue
+			}
+		}
+		break
+	}
+}
+
+func (self *_parser) skipLineWhiteSpace() {
+	for isLineWhiteSpace(self.chr) {
+		self.read()
+	}
+}
+
+func (self *_parser) scanMantissa(base int) {
+	for digitValue(self.chr) < base {
+		self.read()
+	}
+}
+
+func (self *_parser) scanEscape(quote rune) {
+
+	var length, base uint32
+	switch self.chr {
+	//case '0', '1', '2', '3', '4', '5', '6', '7':
+	//    Octal:
+	//    length, base, limit = 3, 8, 255
+	case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', '"', '\'', '0':
+		self.read()
+		return
+	case '\r', '\n', '\u2028', '\u2029':
+		self.scanNewline()
+		return
+	case 'x':
+		self.read()
+		length, base = 2, 16
+	case 'u':
+		self.read()
+		length, base = 4, 16
+	default:
+		self.read() // Always make progress
+		return
+	}
+
+	var value uint32
+	for ; length > 0 && self.chr != quote && self.chr >= 0; length-- {
+		digit := uint32(digitValue(self.chr))
+		if digit >= base {
+			break
+		}
+		value = value*base + digit
+		self.read()
+	}
+}
+
+func (self *_parser) scanString(offset int) (string, error) {
+	// " ' /
+	quote := rune(self.str[offset])
+
+	for self.chr != quote {
+		chr := self.chr
+		if chr == '\n' || chr == '\r' || chr == '\u2028' || chr == '\u2029' || chr < 0 {
+			goto newline
+		}
+		self.read()
+		if chr == '\\' {
+			if quote == '/' {
+				if self.chr == '\n' || self.chr == '\r' || self.chr == '\u2028' || self.chr == '\u2029' || self.chr < 0 {
+					goto newline
+				}
+				self.read()
+			} else {
+				self.scanEscape(quote)
+			}
+		} else if chr == '[' && quote == '/' {
+			// Allow a slash (/) in a bracket character class ([...])
+			// TODO Fix this, this is hacky...
+			quote = -1
+		} else if chr == ']' && quote == -1 {
+			quote = '/'
+		}
+	}
+
+	// " ' /
+	self.read()
+
+	return string(self.str[offset:self.chrOffset]), nil
+
+newline:
+	self.scanNewline()
+	err := "String not terminated"
+	if quote == '/' {
+		err = "Invalid regular expression: missing /"
+		self.error(self.idxOf(offset), err)
+	}
+	return "", errors.New(err)
+}
+
+func (self *_parser) scanNewline() {
+	if self.chr == '\r' {
+		self.read()
+		if self.chr != '\n' {
+			return
+		}
+	}
+	self.read()
+}
+
+func hex2decimal(chr byte) (value rune, ok bool) {
+	{
+		chr := rune(chr)
+		switch {
+		case '0' <= chr && chr <= '9':
+			return chr - '0', true
+		case 'a' <= chr && chr <= 'f':
+			return chr - 'a' + 10, true
+		case 'A' <= chr && chr <= 'F':
+			return chr - 'A' + 10, true
+		}
+		return
+	}
+}
+
+func parseNumberLiteral(literal string) (value interface{}, err error) {
+	// TODO Is Uint okay? What about -MAX_UINT
+	value, err = strconv.ParseInt(literal, 0, 64)
+	if err == nil {
+		return
+	}
+
+	parseIntErr := err // Save this first error, just in case
+
+	value, err = strconv.ParseFloat(literal, 64)
+	if err == nil {
+		return
+	} else if err.(*strconv.NumError).Err == strconv.ErrRange {
+		// Infinity, etc.
+		return value, nil
+	}
+
+	err = parseIntErr
+
+	if err.(*strconv.NumError).Err == strconv.ErrRange {
+		if len(literal) > 2 && literal[0] == '0' && (literal[1] == 'X' || literal[1] == 'x') {
+			// Could just be a very large number (e.g. 0x8000000000000000)
+			var value float64
+			literal = literal[2:]
+			for _, chr := range literal {
+				digit := digitValue(chr)
+				if digit >= 16 {
+					goto error
+				}
+				value = value*16 + float64(digit)
+			}
+			return value, nil
+		}
+	}
+
+error:
+	return nil, errors.New("Illegal numeric literal")
+}
+
+func parseStringLiteral(literal string) (string, error) {
+	// Best case scenario...
+	if literal == "" {
+		return "", nil
+	}
+
+	// Slightly less-best case scenario...
+	if !strings.ContainsRune(literal, '\\') {
+		return literal, nil
+	}
+
+	str := literal
+	buffer := bytes.NewBuffer(make([]byte, 0, 3*len(literal)/2))
+
+	for len(str) > 0 {
+		switch chr := str[0]; {
+		// We do not explicitly handle the case of the quote
+		// value, which can be: " ' /
+		// This assumes we're already passed a partially well-formed literal
+		case chr >= utf8.RuneSelf:
+			chr, size := utf8.DecodeRuneInString(str)
+			buffer.WriteRune(chr)
+			str = str[size:]
+			continue
+		case chr != '\\':
+			buffer.WriteByte(chr)
+			str = str[1:]
+			continue
+		}
+
+		if len(str) <= 1 {
+			panic("len(str) <= 1")
+		}
+		chr := str[1]
+		var value rune
+		if chr >= utf8.RuneSelf {
+			str = str[1:]
+			var size int
+			value, size = utf8.DecodeRuneInString(str)
+			str = str[size:] // \ + <character>
+		} else {
+			str = str[2:] // \<character>
+			switch chr {
+			case 'b':
+				value = '\b'
+			case 'f':
+				value = '\f'
+			case 'n':
+				value = '\n'
+			case 'r':
+				value = '\r'
+			case 't':
+				value = '\t'
+			case 'v':
+				value = '\v'
+			case 'x', 'u':
+				size := 0
+				switch chr {
+				case 'x':
+					size = 2
+				case 'u':
+					size = 4
+				}
+				if len(str) < size {
+					return "", fmt.Errorf("invalid escape: \\%s: len(%q) != %d", string(chr), str, size)
+				}
+				for j := 0; j < size; j++ {
+					decimal, ok := hex2decimal(str[j])
+					if !ok {
+						return "", fmt.Errorf("invalid escape: \\%s: %q", string(chr), str[:size])
+					}
+					value = value<<4 | decimal
+				}
+				str = str[size:]
+				if chr == 'x' {
+					break
+				}
+				if value > utf8.MaxRune {
+					panic("value > utf8.MaxRune")
+				}
+			case '0':
+				if len(str) == 0 || '0' > str[0] || str[0] > '7' {
+					value = 0
+					break
+				}
+				fallthrough
+			case '1', '2', '3', '4', '5', '6', '7':
+				// TODO strict
+				value = rune(chr) - '0'
+				j := 0
+				for ; j < 2; j++ {
+					if len(str) < j+1 {
+						break
+					}
+					chr := str[j]
+					if '0' > chr || chr > '7' {
+						break
+					}
+					decimal := rune(str[j]) - '0'
+					value = (value << 3) | decimal
+				}
+				str = str[j:]
+			case '\\':
+				value = '\\'
+			case '\'', '"':
+				value = rune(chr)
+			case '\r':
+				if len(str) > 0 {
+					if str[0] == '\n' {
+						str = str[1:]
+					}
+				}
+				fallthrough
+			case '\n':
+				continue
+			default:
+				value = rune(chr)
+			}
+		}
+		buffer.WriteRune(value)
+	}
+
+	return buffer.String(), nil
+}
+
+func (self *_parser) scanNumericLiteral(decimalPoint bool) (token.Token, string) {
+
+	offset := self.chrOffset
+	tkn := token.NUMBER
+
+	if decimalPoint {
+		offset--
+		self.scanMantissa(10)
+		goto exponent
+	}
+
+	if self.chr == '0' {
+		offset := self.chrOffset
+		self.read()
+		if self.chr == 'x' || self.chr == 'X' {
+			// Hexadecimal
+			self.read()
+			if isDigit(self.chr, 16) {
+				self.read()
+			} else {
+				return token.ILLEGAL, self.str[offset:self.chrOffset]
+			}
+			self.scanMantissa(16)
+
+			if self.chrOffset-offset <= 2 {
+				// Only "0x" or "0X"
+				self.error(0, "Illegal hexadecimal number")
+			}
+
+			goto hexadecimal
+		} else if self.chr == '.' {
+			// Float
+			goto float
+		} else {
+			// Octal, Float
+			if self.chr == 'e' || self.chr == 'E' {
+				goto exponent
+			}
+			self.scanMantissa(8)
+			if self.chr == '8' || self.chr == '9' {
+				return token.ILLEGAL, self.str[offset:self.chrOffset]
+			}
+			goto octal
+		}
+	}
+
+	self.scanMantissa(10)
+
+float:
+	if self.chr == '.' {
+		self.read()
+		self.scanMantissa(10)
+	}
+
+exponent:
+	if self.chr == 'e' || self.chr == 'E' {
+		self.read()
+		if self.chr == '-' || self.chr == '+' {
+			self.read()
+		}
+		if isDecimalDigit(self.chr) {
+			self.read()
+			self.scanMantissa(10)
+		} else {
+			return token.ILLEGAL, self.str[offset:self.chrOffset]
+		}
+	}
+
+hexadecimal:
+octal:
+	if isIdentifierStart(self.chr) || isDecimalDigit(self.chr) {
+		return token.ILLEGAL, self.str[offset:self.chrOffset]
+	}
+
+	return tkn, self.str[offset:self.chrOffset]
+}
diff --git a/vendor/github.com/robertkrimen/otto/parser/parser.go b/vendor/github.com/robertkrimen/otto/parser/parser.go
new file mode 100644
index 000000000..75b7c500c
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/parser.go
@@ -0,0 +1,344 @@
+/*
+Package parser implements a parser for JavaScript.
+
+    import (
+        "github.com/robertkrimen/otto/parser"
+    )
+
+Parse and return an AST
+
+    filename := "" // A filename is optional
+    src := `
+        // Sample xyzzy example
+        (function(){
+            if (3.14159 > 0) {
+                console.log("Hello, World.");
+                return;
+            }
+
+            var xyzzy = NaN;
+            console.log("Nothing happens.");
+            return xyzzy;
+        })();
+    `
+
+    // Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
+    program, err := parser.ParseFile(nil, filename, src, 0)
+
+Warning
+
+The parser and AST interfaces are still works-in-progress (particularly where
+node types are concerned) and may change in the future.
+
+*/
+package parser
+
+import (
+	"bytes"
+	"encoding/base64"
+	"errors"
+	"io"
+	"io/ioutil"
+
+	"github.com/robertkrimen/otto/ast"
+	"github.com/robertkrimen/otto/file"
+	"github.com/robertkrimen/otto/token"
+	"gopkg.in/sourcemap.v1"
+)
+
+// A Mode value is a set of flags (or 0). They control optional parser functionality.
+type Mode uint
+
+const (
+	IgnoreRegExpErrors Mode = 1 << iota // Ignore RegExp compatibility errors (allow backtracking)
+	StoreComments                       // Store the comments from source to the comments map
+)
+
+type _parser struct {
+	str    string
+	length int
+	base   int
+
+	chr       rune // The current character
+	chrOffset int  // The offset of current character
+	offset    int  // The offset after current character (may be greater than 1)
+
+	idx     file.Idx    // The index of token
+	token   token.Token // The token
+	literal string      // The literal of the token, if any
+
+	scope             *_scope
+	insertSemicolon   bool // If we see a newline, then insert an implicit semicolon
+	implicitSemicolon bool // An implicit semicolon exists
+
+	errors ErrorList
+
+	recover struct {
+		// Scratch when trying to seek to the next statement, etc.
+		idx   file.Idx
+		count int
+	}
+
+	mode Mode
+
+	file *file.File
+
+	comments *ast.Comments
+}
+
+type Parser interface {
+	Scan() (tkn token.Token, literal string, idx file.Idx)
+}
+
+func _newParser(filename, src string, base int, sm *sourcemap.Consumer) *_parser {
+	return &_parser{
+		chr:      ' ', // This is set so we can start scanning by skipping whitespace
+		str:      src,
+		length:   len(src),
+		base:     base,
+		file:     file.NewFile(filename, src, base).WithSourceMap(sm),
+		comments: ast.NewComments(),
+	}
+}
+
+// Returns a new Parser.
+func NewParser(filename, src string) Parser {
+	return _newParser(filename, src, 1, nil)
+}
+
+func ReadSource(filename string, src interface{}) ([]byte, error) {
+	if src != nil {
+		switch src := src.(type) {
+		case string:
+			return []byte(src), nil
+		case []byte:
+			return src, nil
+		case *bytes.Buffer:
+			if src != nil {
+				return src.Bytes(), nil
+			}
+		case io.Reader:
+			var bfr bytes.Buffer
+			if _, err := io.Copy(&bfr, src); err != nil {
+				return nil, err
+			}
+			return bfr.Bytes(), nil
+		}
+		return nil, errors.New("invalid source")
+	}
+	return ioutil.ReadFile(filename)
+}
+
+func ReadSourceMap(filename string, src interface{}) (*sourcemap.Consumer, error) {
+	if src == nil {
+		return nil, nil
+	}
+
+	switch src := src.(type) {
+	case string:
+		return sourcemap.Parse(filename, []byte(src))
+	case []byte:
+		return sourcemap.Parse(filename, src)
+	case *bytes.Buffer:
+		if src != nil {
+			return sourcemap.Parse(filename, src.Bytes())
+		}
+	case io.Reader:
+		var bfr bytes.Buffer
+		if _, err := io.Copy(&bfr, src); err != nil {
+			return nil, err
+		}
+		return sourcemap.Parse(filename, bfr.Bytes())
+	case *sourcemap.Consumer:
+		return src, nil
+	}
+
+	return nil, errors.New("invalid sourcemap type")
+}
+
+func ParseFileWithSourceMap(fileSet *file.FileSet, filename string, javascriptSource, sourcemapSource interface{}, mode Mode) (*ast.Program, error) {
+	src, err := ReadSource(filename, javascriptSource)
+	if err != nil {
+		return nil, err
+	}
+
+	if sourcemapSource == nil {
+		lines := bytes.Split(src, []byte("\n"))
+		lastLine := lines[len(lines)-1]
+		if bytes.HasPrefix(lastLine, []byte("//# sourceMappingURL=data:application/json")) {
+			bits := bytes.SplitN(lastLine, []byte(","), 2)
+			if len(bits) == 2 {
+				if d, err := base64.StdEncoding.DecodeString(string(bits[1])); err == nil {
+					sourcemapSource = d
+				}
+			}
+		}
+	}
+
+	sm, err := ReadSourceMap(filename, sourcemapSource)
+	if err != nil {
+		return nil, err
+	}
+
+	base := 1
+	if fileSet != nil {
+		base = fileSet.AddFile(filename, string(src))
+	}
+
+	parser := _newParser(filename, string(src), base, sm)
+	parser.mode = mode
+	program, err := parser.parse()
+	program.Comments = parser.comments.CommentMap
+
+	return program, err
+}
+
+// ParseFile parses the source code of a single JavaScript/ECMAScript source file and returns
+// the corresponding ast.Program node.
+//
+// If fileSet == nil, ParseFile parses source without a FileSet.
+// If fileSet != nil, ParseFile first adds filename and src to fileSet.
+//
+// The filename argument is optional and is used for labelling errors, etc.
+//
+// src may be a string, a byte slice, a bytes.Buffer, or an io.Reader, but it MUST always be in UTF-8.
+//
+//      // Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
+//      program, err := parser.ParseFile(nil, "", `if (abc > 1) {}`, 0)
+//
+func ParseFile(fileSet *file.FileSet, filename string, src interface{}, mode Mode) (*ast.Program, error) {
+	return ParseFileWithSourceMap(fileSet, filename, src, nil, mode)
+}
+
+// ParseFunction parses a given parameter list and body as a function and returns the
+// corresponding ast.FunctionLiteral node.
+//
+// The parameter list, if any, should be a comma-separated list of identifiers.
+//
+func ParseFunction(parameterList, body string) (*ast.FunctionLiteral, error) {
+
+	src := "(function(" + parameterList + ") {\n" + body + "\n})"
+
+	parser := _newParser("", src, 1, nil)
+	program, err := parser.parse()
+	if err != nil {
+		return nil, err
+	}
+
+	return program.Body[0].(*ast.ExpressionStatement).Expression.(*ast.FunctionLiteral), nil
+}
+
+// Scan reads a single token from the source at the current offset, increments the offset and
+// returns the token.Token token, a string literal representing the value of the token (if applicable)
+// and it's current file.Idx index.
+func (self *_parser) Scan() (tkn token.Token, literal string, idx file.Idx) {
+	return self.scan()
+}
+
+func (self *_parser) slice(idx0, idx1 file.Idx) string {
+	from := int(idx0) - self.base
+	to := int(idx1) - self.base
+	if from >= 0 && to <= len(self.str) {
+		return self.str[from:to]
+	}
+
+	return ""
+}
+
+func (self *_parser) parse() (*ast.Program, error) {
+	self.next()
+	program := self.parseProgram()
+	if false {
+		self.errors.Sort()
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(program, self.comments.FetchAll(), ast.TRAILING)
+	}
+
+	return program, self.errors.Err()
+}
+
+func (self *_parser) next() {
+	self.token, self.literal, self.idx = self.scan()
+}
+
+func (self *_parser) optionalSemicolon() {
+	if self.token == token.SEMICOLON {
+		self.next()
+		return
+	}
+
+	if self.implicitSemicolon {
+		self.implicitSemicolon = false
+		return
+	}
+
+	if self.token != token.EOF && self.token != token.RIGHT_BRACE {
+		self.expect(token.SEMICOLON)
+	}
+}
+
+func (self *_parser) semicolon() {
+	if self.token != token.RIGHT_PARENTHESIS && self.token != token.RIGHT_BRACE {
+		if self.implicitSemicolon {
+			self.implicitSemicolon = false
+			return
+		}
+
+		self.expect(token.SEMICOLON)
+	}
+}
+
+func (self *_parser) idxOf(offset int) file.Idx {
+	return file.Idx(self.base + offset)
+}
+
+func (self *_parser) expect(value token.Token) file.Idx {
+	idx := self.idx
+	if self.token != value {
+		self.errorUnexpectedToken(self.token)
+	}
+	self.next()
+	return idx
+}
+
+func lineCount(str string) (int, int) {
+	line, last := 0, -1
+	pair := false
+	for index, chr := range str {
+		switch chr {
+		case '\r':
+			line += 1
+			last = index
+			pair = true
+			continue
+		case '\n':
+			if !pair {
+				line += 1
+			}
+			last = index
+		case '\u2028', '\u2029':
+			line += 1
+			last = index + 2
+		}
+		pair = false
+	}
+	return line, last
+}
+
+func (self *_parser) position(idx file.Idx) file.Position {
+	position := file.Position{}
+	offset := int(idx) - self.base
+	str := self.str[:offset]
+	position.Filename = self.file.Name()
+	line, last := lineCount(str)
+	position.Line = 1 + line
+	if last >= 0 {
+		position.Column = offset - last
+	} else {
+		position.Column = 1 + len(str)
+	}
+
+	return position
+}
diff --git a/vendor/github.com/robertkrimen/otto/parser/regexp.go b/vendor/github.com/robertkrimen/otto/parser/regexp.go
new file mode 100644
index 000000000..f614dae74
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/regexp.go
@@ -0,0 +1,358 @@
+package parser
+
+import (
+	"bytes"
+	"fmt"
+	"strconv"
+)
+
+type _RegExp_parser struct {
+	str    string
+	length int
+
+	chr       rune // The current character
+	chrOffset int  // The offset of current character
+	offset    int  // The offset after current character (may be greater than 1)
+
+	errors  []error
+	invalid bool // The input is an invalid JavaScript RegExp
+
+	goRegexp *bytes.Buffer
+}
+
+// TransformRegExp transforms a JavaScript pattern into  a Go "regexp" pattern.
+//
+// re2 (Go) cannot do backtracking, so the presence of a lookahead (?=) (?!) or
+// backreference (\1, \2, ...) will cause an error.
+//
+// re2 (Go) has a different definition for \s: [\t\n\f\r ].
+// The JavaScript definition, on the other hand, also includes \v, Unicode "Separator, Space", etc.
+//
+// If the pattern is invalid (not valid even in JavaScript), then this function
+// returns the empty string and an error.
+//
+// If the pattern is valid, but incompatible (contains a lookahead or backreference),
+// then this function returns the transformation (a non-empty string) AND an error.
+func TransformRegExp(pattern string) (string, error) {
+
+	if pattern == "" {
+		return "", nil
+	}
+
+	// TODO If without \, if without (?=, (?!, then another shortcut
+
+	parser := _RegExp_parser{
+		str:      pattern,
+		length:   len(pattern),
+		goRegexp: bytes.NewBuffer(make([]byte, 0, 3*len(pattern)/2)),
+	}
+	parser.read() // Pull in the first character
+	parser.scan()
+	var err error
+	if len(parser.errors) > 0 {
+		err = parser.errors[0]
+	}
+	if parser.invalid {
+		return "", err
+	}
+
+	// Might not be re2 compatible, but is still a valid JavaScript RegExp
+	return parser.goRegexp.String(), err
+}
+
+func (self *_RegExp_parser) scan() {
+	for self.chr != -1 {
+		switch self.chr {
+		case '\\':
+			self.read()
+			self.scanEscape(false)
+		case '(':
+			self.pass()
+			self.scanGroup()
+		case '[':
+			self.pass()
+			self.scanBracket()
+		case ')':
+			self.error(-1, "Unmatched ')'")
+			self.invalid = true
+			self.pass()
+		default:
+			self.pass()
+		}
+	}
+}
+
+// (...)
+func (self *_RegExp_parser) scanGroup() {
+	str := self.str[self.chrOffset:]
+	if len(str) > 1 { // A possibility of (?= or (?!
+		if str[0] == '?' {
+			if str[1] == '=' || str[1] == '!' {
+				self.error(-1, "re2: Invalid (%s) <lookahead>", self.str[self.chrOffset:self.chrOffset+2])
+			}
+		}
+	}
+	for self.chr != -1 && self.chr != ')' {
+		switch self.chr {
+		case '\\':
+			self.read()
+			self.scanEscape(false)
+		case '(':
+			self.pass()
+			self.scanGroup()
+		case '[':
+			self.pass()
+			self.scanBracket()
+		default:
+			self.pass()
+			continue
+		}
+	}
+	if self.chr != ')' {
+		self.error(-1, "Unterminated group")
+		self.invalid = true
+		return
+	}
+	self.pass()
+}
+
+// [...]
+func (self *_RegExp_parser) scanBracket() {
+	for self.chr != -1 {
+		if self.chr == ']' {
+			break
+		} else if self.chr == '\\' {
+			self.read()
+			self.scanEscape(true)
+			continue
+		}
+		self.pass()
+	}
+	if self.chr != ']' {
+		self.error(-1, "Unterminated character class")
+		self.invalid = true
+		return
+	}
+	self.pass()
+}
+
+// \...
+func (self *_RegExp_parser) scanEscape(inClass bool) {
+	offset := self.chrOffset
+
+	var length, base uint32
+	switch self.chr {
+
+	case '0', '1', '2', '3', '4', '5', '6', '7':
+		var value int64
+		size := 0
+		for {
+			digit := int64(digitValue(self.chr))
+			if digit >= 8 {
+				// Not a valid digit
+				break
+			}
+			value = value*8 + digit
+			self.read()
+			size += 1
+		}
+		if size == 1 { // The number of characters read
+			_, err := self.goRegexp.Write([]byte{'\\', byte(value) + '0'})
+			if err != nil {
+				self.errors = append(self.errors, err)
+			}
+			if value != 0 {
+				// An invalid backreference
+				self.error(-1, "re2: Invalid \\%d <backreference>", value)
+			}
+			return
+		}
+		tmp := []byte{'\\', 'x', '0', 0}
+		if value >= 16 {
+			tmp = tmp[0:2]
+		} else {
+			tmp = tmp[0:3]
+		}
+		tmp = strconv.AppendInt(tmp, value, 16)
+		_, err := self.goRegexp.Write(tmp)
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+		return
+
+	case '8', '9':
+		size := 0
+		for {
+			digit := digitValue(self.chr)
+			if digit >= 10 {
+				// Not a valid digit
+				break
+			}
+			self.read()
+			size += 1
+		}
+		err := self.goRegexp.WriteByte('\\')
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+		_, err = self.goRegexp.WriteString(self.str[offset:self.chrOffset])
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+		self.error(-1, "re2: Invalid \\%s <backreference>", self.str[offset:self.chrOffset])
+		return
+
+	case 'x':
+		self.read()
+		length, base = 2, 16
+
+	case 'u':
+		self.read()
+		length, base = 4, 16
+
+	case 'b':
+		if inClass {
+			_, err := self.goRegexp.Write([]byte{'\\', 'x', '0', '8'})
+			if err != nil {
+				self.errors = append(self.errors, err)
+			}
+			self.read()
+			return
+		}
+		fallthrough
+
+	case 'B':
+		fallthrough
+
+	case 'd', 'D', 's', 'S', 'w', 'W':
+		// This is slightly broken, because ECMAScript
+		// includes \v in \s, \S, while re2 does not
+		fallthrough
+
+	case '\\':
+		fallthrough
+
+	case 'f', 'n', 'r', 't', 'v':
+		err := self.goRegexp.WriteByte('\\')
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+		self.pass()
+		return
+
+	case 'c':
+		self.read()
+		var value int64
+		if 'a' <= self.chr && self.chr <= 'z' {
+			value = int64(self.chr) - 'a' + 1
+		} else if 'A' <= self.chr && self.chr <= 'Z' {
+			value = int64(self.chr) - 'A' + 1
+		} else {
+			err := self.goRegexp.WriteByte('c')
+			if err != nil {
+				self.errors = append(self.errors, err)
+			}
+			return
+		}
+		tmp := []byte{'\\', 'x', '0', 0}
+		if value >= 16 {
+			tmp = tmp[0:2]
+		} else {
+			tmp = tmp[0:3]
+		}
+		tmp = strconv.AppendInt(tmp, value, 16)
+		_, err := self.goRegexp.Write(tmp)
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+		self.read()
+		return
+
+	default:
+		// $ is an identifier character, so we have to have
+		// a special case for it here
+		if self.chr == '$' || !isIdentifierPart(self.chr) {
+			// A non-identifier character needs escaping
+			err := self.goRegexp.WriteByte('\\')
+			if err != nil {
+				self.errors = append(self.errors, err)
+			}
+		} else {
+			// Unescape the character for re2
+		}
+		self.pass()
+		return
+	}
+
+	// Otherwise, we're a \u.... or \x...
+	valueOffset := self.chrOffset
+
+	var value uint32
+	{
+		length := length
+		for ; length > 0; length-- {
+			digit := uint32(digitValue(self.chr))
+			if digit >= base {
+				// Not a valid digit
+				goto skip
+			}
+			value = value*base + digit
+			self.read()
+		}
+	}
+
+	if length == 4 {
+		_, err := self.goRegexp.Write([]byte{
+			'\\',
+			'x',
+			'{',
+			self.str[valueOffset+0],
+			self.str[valueOffset+1],
+			self.str[valueOffset+2],
+			self.str[valueOffset+3],
+			'}',
+		})
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+	} else if length == 2 {
+		_, err := self.goRegexp.Write([]byte{
+			'\\',
+			'x',
+			self.str[valueOffset+0],
+			self.str[valueOffset+1],
+		})
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+	} else {
+		// Should never, ever get here...
+		self.error(-1, "re2: Illegal branch in scanEscape")
+		goto skip
+	}
+
+	return
+
+skip:
+	_, err := self.goRegexp.WriteString(self.str[offset:self.chrOffset])
+	if err != nil {
+		self.errors = append(self.errors, err)
+	}
+}
+
+func (self *_RegExp_parser) pass() {
+	if self.chr != -1 {
+		_, err := self.goRegexp.WriteRune(self.chr)
+		if err != nil {
+			self.errors = append(self.errors, err)
+		}
+	}
+	self.read()
+}
+
+// TODO Better error reporting, use the offset, etc.
+func (self *_RegExp_parser) error(offset int, msg string, msgValues ...interface{}) error {
+	err := fmt.Errorf(msg, msgValues...)
+	self.errors = append(self.errors, err)
+	return err
+}
diff --git a/vendor/github.com/robertkrimen/otto/parser/scope.go b/vendor/github.com/robertkrimen/otto/parser/scope.go
new file mode 100644
index 000000000..e1dbdda13
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/scope.go
@@ -0,0 +1,44 @@
+package parser
+
+import (
+	"github.com/robertkrimen/otto/ast"
+)
+
+type _scope struct {
+	outer           *_scope
+	allowIn         bool
+	inIteration     bool
+	inSwitch        bool
+	inFunction      bool
+	declarationList []ast.Declaration
+
+	labels []string
+}
+
+func (self *_parser) openScope() {
+	self.scope = &_scope{
+		outer:   self.scope,
+		allowIn: true,
+	}
+}
+
+func (self *_parser) closeScope() {
+	self.scope = self.scope.outer
+}
+
+func (self *_scope) declare(declaration ast.Declaration) {
+	self.declarationList = append(self.declarationList, declaration)
+}
+
+func (self *_scope) hasLabel(name string) bool {
+	for _, label := range self.labels {
+		if label == name {
+			return true
+		}
+	}
+	if self.outer != nil && !self.inFunction {
+		// Crossing a function boundary to look for a label is verboten
+		return self.outer.hasLabel(name)
+	}
+	return false
+}
diff --git a/vendor/github.com/robertkrimen/otto/parser/statement.go b/vendor/github.com/robertkrimen/otto/parser/statement.go
new file mode 100644
index 000000000..6ff19d975
--- /dev/null
+++ b/vendor/github.com/robertkrimen/otto/parser/statement.go
@@ -0,0 +1,938 @@
+package parser
+
+import (
+	"github.com/robertkrimen/otto/ast"
+	"github.com/robertkrimen/otto/token"
+)
+
+func (self *_parser) parseBlockStatement() *ast.BlockStatement {
+	node := &ast.BlockStatement{}
+
+	// Find comments before the leading brace
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, self.comments.FetchAll(), ast.LEADING)
+		self.comments.Unset()
+	}
+
+	node.LeftBrace = self.expect(token.LEFT_BRACE)
+	node.List = self.parseStatementList()
+
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+		self.comments.CommentMap.AddComments(node, self.comments.FetchAll(), ast.FINAL)
+		self.comments.AfterBlock()
+	}
+
+	node.RightBrace = self.expect(token.RIGHT_BRACE)
+
+	// Find comments after the trailing brace
+	if self.mode&StoreComments != 0 {
+		self.comments.ResetLineBreak()
+		self.comments.CommentMap.AddComments(node, self.comments.Fetch(), ast.TRAILING)
+	}
+
+	return node
+}
+
+func (self *_parser) parseEmptyStatement() ast.Statement {
+	idx := self.expect(token.SEMICOLON)
+	return &ast.EmptyStatement{Semicolon: idx}
+}
+
+func (self *_parser) parseStatementList() (list []ast.Statement) {
+	for self.token != token.RIGHT_BRACE && self.token != token.EOF {
+		statement := self.parseStatement()
+		list = append(list, statement)
+	}
+
+	return
+}
+
+func (self *_parser) parseStatement() ast.Statement {
+
+	if self.token == token.EOF {
+		self.errorUnexpectedToken(self.token)
+		return &ast.BadStatement{From: self.idx, To: self.idx + 1}
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.ResetLineBreak()
+	}
+
+	switch self.token {
+	case token.SEMICOLON:
+		return self.parseEmptyStatement()
+	case token.LEFT_BRACE:
+		return self.parseBlockStatement()
+	case token.IF:
+		return self.parseIfStatement()
+	case token.DO:
+		statement := self.parseDoWhileStatement()
+		self.comments.PostProcessNode(statement)
+		return statement
+	case token.WHILE:
+		return self.parseWhileStatement()
+	case token.FOR:
+		return self.parseForOrForInStatement()
+	case token.BREAK:
+		return self.parseBreakStatement()
+	case token.CONTINUE:
+		return self.parseContinueStatement()
+	case token.DEBUGGER:
+		return self.parseDebuggerStatement()
+	case token.WITH:
+		return self.parseWithStatement()
+	case token.VAR:
+		return self.parseVariableStatement()
+	case token.FUNCTION:
+		return self.parseFunctionStatement()
+	case token.SWITCH:
+		return self.parseSwitchStatement()
+	case token.RETURN:
+		return self.parseReturnStatement()
+	case token.THROW:
+		return self.parseThrowStatement()
+	case token.TRY:
+		return self.parseTryStatement()
+	}
+
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+
+	expression := self.parseExpression()
+
+	if identifier, isIdentifier := expression.(*ast.Identifier); isIdentifier && self.token == token.COLON {
+		// LabelledStatement
+		colon := self.idx
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next() // :
+
+		label := identifier.Name
+		for _, value := range self.scope.labels {
+			if label == value {
+				self.error(identifier.Idx0(), "Label '%s' already exists", label)
+			}
+		}
+		var labelComments []*ast.Comment
+		if self.mode&StoreComments != 0 {
+			labelComments = self.comments.FetchAll()
+		}
+		self.scope.labels = append(self.scope.labels, label) // Push the label
+		statement := self.parseStatement()
+		self.scope.labels = self.scope.labels[:len(self.scope.labels)-1] // Pop the label
+		exp := &ast.LabelledStatement{
+			Label:     identifier,
+			Colon:     colon,
+			Statement: statement,
+		}
+		if self.mode&StoreComments != 0 {
+			self.comments.CommentMap.AddComments(exp, labelComments, ast.LEADING)
+		}
+
+		return exp
+	}
+
+	self.optionalSemicolon()
+
+	statement := &ast.ExpressionStatement{
+		Expression: expression,
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(statement, comments, ast.LEADING)
+	}
+	return statement
+}
+
+func (self *_parser) parseTryStatement() ast.Statement {
+	var tryComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		tryComments = self.comments.FetchAll()
+	}
+	node := &ast.TryStatement{
+		Try:  self.expect(token.TRY),
+		Body: self.parseBlockStatement(),
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, tryComments, ast.LEADING)
+		self.comments.CommentMap.AddComments(node.Body, self.comments.FetchAll(), ast.TRAILING)
+	}
+
+	if self.token == token.CATCH {
+		catch := self.idx
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+		self.expect(token.LEFT_PARENTHESIS)
+		if self.token != token.IDENTIFIER {
+			self.expect(token.IDENTIFIER)
+			self.nextStatement()
+			return &ast.BadStatement{From: catch, To: self.idx}
+		} else {
+			identifier := self.parseIdentifier()
+			self.expect(token.RIGHT_PARENTHESIS)
+			node.Catch = &ast.CatchStatement{
+				Catch:     catch,
+				Parameter: identifier,
+				Body:      self.parseBlockStatement(),
+			}
+
+			if self.mode&StoreComments != 0 {
+				self.comments.CommentMap.AddComments(node.Catch.Body, self.comments.FetchAll(), ast.TRAILING)
+			}
+		}
+	}
+
+	if self.token == token.FINALLY {
+		if self.mode&StoreComments != 0 {
+			self.comments.Unset()
+		}
+		self.next()
+		if self.mode&StoreComments != 0 {
+			tryComments = self.comments.FetchAll()
+		}
+
+		node.Finally = self.parseBlockStatement()
+
+		if self.mode&StoreComments != 0 {
+			self.comments.CommentMap.AddComments(node.Finally, tryComments, ast.LEADING)
+		}
+	}
+
+	if node.Catch == nil && node.Finally == nil {
+		self.error(node.Try, "Missing catch or finally after try")
+		return &ast.BadStatement{From: node.Try, To: node.Body.Idx1()}
+	}
+
+	return node
+}
+
+func (self *_parser) parseFunctionParameterList() *ast.ParameterList {
+	opening := self.expect(token.LEFT_PARENTHESIS)
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	var list []*ast.Identifier
+	for self.token != token.RIGHT_PARENTHESIS && self.token != token.EOF {
+		if self.token != token.IDENTIFIER {
+			self.expect(token.IDENTIFIER)
+		} else {
+			identifier := self.parseIdentifier()
+			list = append(list, identifier)
+		}
+		if self.token != token.RIGHT_PARENTHESIS {
+			if self.mode&StoreComments != 0 {
+				self.comments.Unset()
+			}
+			self.expect(token.COMMA)
+		}
+	}
+	closing := self.expect(token.RIGHT_PARENTHESIS)
+
+	return &ast.ParameterList{
+		Opening: opening,
+		List:    list,
+		Closing: closing,
+	}
+}
+
+func (self *_parser) parseParameterList() (list []string) {
+	for self.token != token.EOF {
+		if self.token != token.IDENTIFIER {
+			self.expect(token.IDENTIFIER)
+		}
+		list = append(list, self.literal)
+		self.next()
+		if self.token != token.EOF {
+			self.expect(token.COMMA)
+		}
+	}
+	return
+}
+
+func (self *_parser) parseFunctionStatement() *ast.FunctionStatement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	function := &ast.FunctionStatement{
+		Function: self.parseFunction(true),
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(function, comments, ast.LEADING)
+	}
+
+	return function
+}
+
+func (self *_parser) parseFunction(declaration bool) *ast.FunctionLiteral {
+
+	node := &ast.FunctionLiteral{
+		Function: self.expect(token.FUNCTION),
+	}
+
+	var name *ast.Identifier
+	if self.token == token.IDENTIFIER {
+		name = self.parseIdentifier()
+		if declaration {
+			self.scope.declare(&ast.FunctionDeclaration{
+				Function: node,
+			})
+		}
+	} else if declaration {
+		// Use expect error handling
+		self.expect(token.IDENTIFIER)
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	node.Name = name
+	node.ParameterList = self.parseFunctionParameterList()
+	self.parseFunctionBlock(node)
+	node.Source = self.slice(node.Idx0(), node.Idx1())
+
+	return node
+}
+
+func (self *_parser) parseFunctionBlock(node *ast.FunctionLiteral) {
+	{
+		self.openScope()
+		inFunction := self.scope.inFunction
+		self.scope.inFunction = true
+		defer func() {
+			self.scope.inFunction = inFunction
+			self.closeScope()
+		}()
+		node.Body = self.parseBlockStatement()
+		node.DeclarationList = self.scope.declarationList
+	}
+}
+
+func (self *_parser) parseDebuggerStatement() ast.Statement {
+	idx := self.expect(token.DEBUGGER)
+
+	node := &ast.DebuggerStatement{
+		Debugger: idx,
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, self.comments.FetchAll(), ast.TRAILING)
+	}
+
+	self.semicolon()
+	return node
+}
+
+func (self *_parser) parseReturnStatement() ast.Statement {
+	idx := self.expect(token.RETURN)
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+
+	if !self.scope.inFunction {
+		self.error(idx, "Illegal return statement")
+		self.nextStatement()
+		return &ast.BadStatement{From: idx, To: self.idx}
+	}
+
+	node := &ast.ReturnStatement{
+		Return: idx,
+	}
+
+	if !self.implicitSemicolon && self.token != token.SEMICOLON && self.token != token.RIGHT_BRACE && self.token != token.EOF {
+		node.Argument = self.parseExpression()
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+	}
+
+	self.semicolon()
+
+	return node
+}
+
+func (self *_parser) parseThrowStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	idx := self.expect(token.THROW)
+
+	if self.implicitSemicolon {
+		if self.chr == -1 { // Hackish
+			self.error(idx, "Unexpected end of input")
+		} else {
+			self.error(idx, "Illegal newline after throw")
+		}
+		self.nextStatement()
+		return &ast.BadStatement{From: idx, To: self.idx}
+	}
+
+	node := &ast.ThrowStatement{
+		Argument: self.parseExpression(),
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+	}
+
+	self.semicolon()
+
+	return node
+}
+
+func (self *_parser) parseSwitchStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	self.expect(token.SWITCH)
+	if self.mode&StoreComments != 0 {
+		comments = append(comments, self.comments.FetchAll()...)
+	}
+	self.expect(token.LEFT_PARENTHESIS)
+	node := &ast.SwitchStatement{
+		Discriminant: self.parseExpression(),
+		Default:      -1,
+	}
+	self.expect(token.RIGHT_PARENTHESIS)
+	if self.mode&StoreComments != 0 {
+		comments = append(comments, self.comments.FetchAll()...)
+	}
+
+	self.expect(token.LEFT_BRACE)
+
+	inSwitch := self.scope.inSwitch
+	self.scope.inSwitch = true
+	defer func() {
+		self.scope.inSwitch = inSwitch
+	}()
+
+	for index := 0; self.token != token.EOF; index++ {
+		if self.token == token.RIGHT_BRACE {
+			self.next()
+			break
+		}
+
+		clause := self.parseCaseStatement()
+		if clause.Test == nil {
+			if node.Default != -1 {
+				self.error(clause.Case, "Already saw a default in switch")
+			}
+			node.Default = index
+		}
+		node.Body = append(node.Body, clause)
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+	}
+
+	return node
+}
+
+func (self *_parser) parseWithStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	self.expect(token.WITH)
+	var withComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		withComments = self.comments.FetchAll()
+	}
+
+	self.expect(token.LEFT_PARENTHESIS)
+
+	node := &ast.WithStatement{
+		Object: self.parseExpression(),
+	}
+	self.expect(token.RIGHT_PARENTHESIS)
+
+	if self.mode&StoreComments != 0 {
+		//comments = append(comments, self.comments.FetchAll()...)
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+		self.comments.CommentMap.AddComments(node, withComments, ast.WITH)
+	}
+
+	node.Body = self.parseStatement()
+
+	return node
+}
+
+func (self *_parser) parseCaseStatement() *ast.CaseStatement {
+	node := &ast.CaseStatement{
+		Case: self.idx,
+	}
+
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+		self.comments.Unset()
+	}
+
+	if self.token == token.DEFAULT {
+		self.next()
+	} else {
+		self.expect(token.CASE)
+		node.Test = self.parseExpression()
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	self.expect(token.COLON)
+
+	for {
+		if self.token == token.EOF ||
+			self.token == token.RIGHT_BRACE ||
+			self.token == token.CASE ||
+			self.token == token.DEFAULT {
+			break
+		}
+		consequent := self.parseStatement()
+		node.Consequent = append(node.Consequent, consequent)
+	}
+
+	// Link the comments to the case statement
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+	}
+
+	return node
+}
+
+func (self *_parser) parseIterationStatement() ast.Statement {
+	inIteration := self.scope.inIteration
+	self.scope.inIteration = true
+	defer func() {
+		self.scope.inIteration = inIteration
+	}()
+	return self.parseStatement()
+}
+
+func (self *_parser) parseForIn(into ast.Expression) *ast.ForInStatement {
+
+	// Already have consumed "<into> in"
+
+	source := self.parseExpression()
+	self.expect(token.RIGHT_PARENTHESIS)
+	body := self.parseIterationStatement()
+
+	forin := &ast.ForInStatement{
+		Into:   into,
+		Source: source,
+		Body:   body,
+	}
+
+	return forin
+}
+
+func (self *_parser) parseFor(initializer ast.Expression) *ast.ForStatement {
+
+	// Already have consumed "<initializer> ;"
+
+	var test, update ast.Expression
+
+	if self.token != token.SEMICOLON {
+		test = self.parseExpression()
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	self.expect(token.SEMICOLON)
+
+	if self.token != token.RIGHT_PARENTHESIS {
+		update = self.parseExpression()
+	}
+	self.expect(token.RIGHT_PARENTHESIS)
+	body := self.parseIterationStatement()
+
+	forstatement := &ast.ForStatement{
+		Initializer: initializer,
+		Test:        test,
+		Update:      update,
+		Body:        body,
+	}
+
+	return forstatement
+}
+
+func (self *_parser) parseForOrForInStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	idx := self.expect(token.FOR)
+	var forComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		forComments = self.comments.FetchAll()
+	}
+	self.expect(token.LEFT_PARENTHESIS)
+
+	var left []ast.Expression
+
+	forIn := false
+	if self.token != token.SEMICOLON {
+
+		allowIn := self.scope.allowIn
+		self.scope.allowIn = false
+		if self.token == token.VAR {
+			var_ := self.idx
+			var varComments []*ast.Comment
+			if self.mode&StoreComments != 0 {
+				varComments = self.comments.FetchAll()
+				self.comments.Unset()
+			}
+			self.next()
+			list := self.parseVariableDeclarationList(var_)
+			if len(list) == 1 && self.token == token.IN {
+				if self.mode&StoreComments != 0 {
+					self.comments.Unset()
+				}
+				self.next() // in
+				forIn = true
+				left = []ast.Expression{list[0]} // There is only one declaration
+			} else {
+				left = list
+			}
+			if self.mode&StoreComments != 0 {
+				self.comments.CommentMap.AddComments(left[0], varComments, ast.LEADING)
+			}
+		} else {
+			left = append(left, self.parseExpression())
+			if self.token == token.IN {
+				self.next()
+				forIn = true
+			}
+		}
+		self.scope.allowIn = allowIn
+	}
+
+	if forIn {
+		switch left[0].(type) {
+		case *ast.Identifier, *ast.DotExpression, *ast.BracketExpression, *ast.VariableExpression:
+			// These are all acceptable
+		default:
+			self.error(idx, "Invalid left-hand side in for-in")
+			self.nextStatement()
+			return &ast.BadStatement{From: idx, To: self.idx}
+		}
+
+		forin := self.parseForIn(left[0])
+		if self.mode&StoreComments != 0 {
+			self.comments.CommentMap.AddComments(forin, comments, ast.LEADING)
+			self.comments.CommentMap.AddComments(forin, forComments, ast.FOR)
+		}
+		return forin
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.Unset()
+	}
+	self.expect(token.SEMICOLON)
+	initializer := &ast.SequenceExpression{Sequence: left}
+	forstatement := self.parseFor(initializer)
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(forstatement, comments, ast.LEADING)
+		self.comments.CommentMap.AddComments(forstatement, forComments, ast.FOR)
+	}
+	return forstatement
+}
+
+func (self *_parser) parseVariableStatement() *ast.VariableStatement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	idx := self.expect(token.VAR)
+
+	list := self.parseVariableDeclarationList(idx)
+
+	statement := &ast.VariableStatement{
+		Var:  idx,
+		List: list,
+	}
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(statement, comments, ast.LEADING)
+		self.comments.Unset()
+	}
+	self.semicolon()
+
+	return statement
+}
+
+func (self *_parser) parseDoWhileStatement() ast.Statement {
+	inIteration := self.scope.inIteration
+	self.scope.inIteration = true
+	defer func() {
+		self.scope.inIteration = inIteration
+	}()
+
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	self.expect(token.DO)
+	var doComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		doComments = self.comments.FetchAll()
+	}
+
+	node := &ast.DoWhileStatement{}
+	if self.token == token.LEFT_BRACE {
+		node.Body = self.parseBlockStatement()
+	} else {
+		node.Body = self.parseStatement()
+	}
+
+	self.expect(token.WHILE)
+	var whileComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		whileComments = self.comments.FetchAll()
+	}
+	self.expect(token.LEFT_PARENTHESIS)
+	node.Test = self.parseExpression()
+	self.expect(token.RIGHT_PARENTHESIS)
+
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+		self.comments.CommentMap.AddComments(node, doComments, ast.DO)
+		self.comments.CommentMap.AddComments(node, whileComments, ast.WHILE)
+	}
+
+	return node
+}
+
+func (self *_parser) parseWhileStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	self.expect(token.WHILE)
+
+	var whileComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		whileComments = self.comments.FetchAll()
+	}
+
+	self.expect(token.LEFT_PARENTHESIS)
+	node := &ast.WhileStatement{
+		Test: self.parseExpression(),
+	}
+	self.expect(token.RIGHT_PARENTHESIS)
+	node.Body = self.parseIterationStatement()
+
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+		self.comments.CommentMap.AddComments(node, whileComments, ast.WHILE)
+	}
+
+	return node
+}
+
+func (self *_parser) parseIfStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	self.expect(token.IF)
+	var ifComments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		ifComments = self.comments.FetchAll()
+	}
+
+	self.expect(token.LEFT_PARENTHESIS)
+	node := &ast.IfStatement{
+		Test: self.parseExpression(),
+	}
+	self.expect(token.RIGHT_PARENTHESIS)
+	if self.token == token.LEFT_BRACE {
+		node.Consequent = self.parseBlockStatement()
+	} else {
+		node.Consequent = self.parseStatement()
+	}
+
+	if self.token == token.ELSE {
+		self.next()
+		node.Alternate = self.parseStatement()
+	}
+
+	if self.mode&StoreComments != 0 {
+		self.comments.CommentMap.AddComments(node, comments, ast.LEADING)
+		self.comments.CommentMap.AddComments(node, ifComments, ast.IF)
+	}
+
+	return node
+}
+
+func (self *_parser) parseSourceElement() ast.Statement {
+	statement := self.parseStatement()
+	//self.comments.Unset()
+	return statement
+}
+
+func (self *_parser) parseSourceElements() []ast.Statement {
+	body := []ast.Statement(nil)
+
+	for {
+		if self.token != token.STRING {
+			break
+		}
+		body = append(body, self.parseSourceElement())
+	}
+
+	for self.token != token.EOF {
+		body = append(body, self.parseSourceElement())
+	}
+
+	return body
+}
+
+func (self *_parser) parseProgram() *ast.Program {
+	self.openScope()
+	defer self.closeScope()
+	return &ast.Program{
+		Body:            self.parseSourceElements(),
+		DeclarationList: self.scope.declarationList,
+		File:            self.file,
+	}
+}
+
+func (self *_parser) parseBreakStatement() ast.Statement {
+	var comments []*ast.Comment
+	if self.mode&StoreComments != 0 {
+		comments = self.comments.FetchAll()
+	}
+	idx := self.expect(token.BREAK)
+	semicolon := self.implicitSemicolon
+	if self.token == token.SEMICOLON {
+		semicolon = true
+		self.next()
+	}
+
+	if semicolon || self.token == token.RIGHT_BRACE {
+		self.implicitSemicolon = false
+		if !self.scope.inIteration && !self.scope.inSwitch {
+			goto illegal
+		}
+		breakStatement := &ast.BranchStatement{
+			Idx:   idx,
+			Token: token.BREAK,
+		}
+
+		if self.mode&StoreComments != 0 {
+			self.comments.CommentMap.AddComments(breakStatement, comments, ast.LEADING)
+			self.comments.CommentMap.AddComments(breakStatement, self.comments.FetchAll(), ast.TRAILING)
+		}
+
+		return breakStatement
+	}
+
+	if self.token == token.IDENTIFIER {
+		identifier := self.parseIdentifier()
+		if !self.scope.hasLabel(identifier.Name) {
+			self.error(idx, "Undefined label '%s'", identifier.Name)
+			return &ast.BadStatement{From: idx, To: identifier.Idx1()}
+		}
+		self.semicolon()
+		breakStatement := &ast.BranchStatement{
+			Idx:   idx,
+			Token: token.BREAK,
+			Label: identifier,
+		}
+		if self.mode&StoreComments != 0 {
+			self.comments.CommentMap.AddComments(breakStatement, comments, ast.LEADING)
+		}
+
+		return breakStatement
+	}
+
+	self.expect(token.IDENTIFIER)
+
+illegal:
+	self.error(idx, "Illegal break statement")
+	self.nextStatement()
+	return &ast.BadStatement{From: idx, To: self.idx}
+}
+
+func (self *_parser) parseContinueStatement() ast.Statement {
+	idx := self.expect(token.CONTINUE)
+	semicolon := self.implicitSemicolon
+	if self.token == token.SEMICOLON {
+		semicolon = true
+		self.next()
+	}
+
+	if semicolon || self.token == token.RIGHT_BRACE {
+		self.implicitSemicolon = false
+		if !self.scope.inIteration {
+			goto illegal
+		}
+		return &ast.BranchStatement{
+			Idx:   idx,
+			Token: token.CONTINUE,
+		}
+	}
+
+	if self.token == token.IDENTIFIER {
+		identifier := self.parseIdentifier()
+		if !self.scope.hasLabel(identifier.Name) {
+			self.error(idx, "Undefined label '%s'", identifier.Name)
+			return &ast.BadStatement{From: idx, To: identifier.Idx1()}
+		}
+		if !self.scope.inIteration {
+			goto illegal
+		}
+		self.semicolon()
+		return &ast.BranchStatement{
+			Idx:   idx,
+			Token: token.CONTINUE,
+			Label: identifier,
+		}
+	}
+
+	self.expect(token.IDENTIFIER)
+
+illegal:
+	self.error(idx, "Illegal continue statement")
+	self.nextStatement()
+	return &ast.BadStatement{From: idx, To: self.idx}
+}
+
+// Find the next statement after an error (recover)
+func (self *_parser) nextStatement() {
+	for {
+		switch self.token {
+		case token.BREAK, token.CONTINUE,
+			token.FOR, token.IF, token.RETURN, token.SWITCH,
+			token.VAR, token.DO, token.TRY, token.WITH,
+			token.WHILE, token.THROW, token.CATCH, token.FINALLY:
+			// Return only if parser made some progress since last
+			// sync or if it has not reached 10 next calls without
+			// progress. Otherwise consume at least one token to
+			// avoid an endless parser loop
+			if self.idx == self.recover.idx && self.recover.count < 10 {
+				self.recover.count++
+				return
+			}
+			if self.idx > self.recover.idx {
+				self.recover.idx = self.idx
+				self.recover.count = 0
+				return
+			}
+			// Reaching here indicates a parser bug, likely an
+			// incorrect token list in this function, but it only
+			// leads to skipping of possibly correct code if a
+			// previous error is present, and thus is preferred
+			// over a non-terminating parse.
+		case token.EOF:
+			return
+		}
+		self.next()
+	}
+}