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 // Acorn is a tiny, fast JavaScript parser written in JavaScript.

 //

 // Acorn was written by Marijn Haverbeke and released under an MIT

 // license. The Unicode regexps (for identifiers and whitespace) were

 // taken from [Esprima](http://esprima.org) by Ariya Hidayat.

 //

 // Git repositories for Acorn are available at

 //

 //     http://marijnhaverbeke.nl/git/acorn

 //     https://github.com/marijnh/acorn.git

 //

 // Please use the [github bug tracker][ghbt] to report issues.

 //

 // [ghbt]: https://github.com/marijnh/acorn/issues

 //

 // This file defines the main parser interface. The library also comes

 // with a [error-tolerant parser][dammit] and an

 // [abstract syntax tree walker][walk], defined in other files.

 //

 // [dammit]: acorn_loose.js

 // [walk]: util/walk.js

 (function(root, mod) {

   if (typeof exports == "object" && typeof module == "object") return mod(exports); // CommonJS

   if (typeof define == "function" && define.amd) return define(["exports"], mod); // AMD

   mod(root.acorn || (root.acorn = {})); // Plain browser env

 })(this, function(exports) {

   "use strict";

   exports.version = "0.4.1";

   // The main exported interface (under `self.acorn` when in the

   // browser) is a `parse` function that takes a code string and

   // returns an abstract syntax tree as specified by [Mozilla parser

   // API][api], with the caveat that the SpiderMonkey-specific syntax

   // (`let`, `yield`, inline XML, etc) is not recognized.

   //

   // [api]: https://developer.mozilla.org/en-US/docs/SpiderMonkey/Parser_API

   var options, input, inputLen, sourceFile;

   exports.parse = function(inpt, opts) {

     input = String(inpt); inputLen = input.length;

     setOptions(opts);

     initTokenState();

     return parseTopLevel(options.program);

   };

   // A second optional argument can be given to further configure

   // the parser process. These options are recognized:

   var defaultOptions = exports.defaultOptions = {

     // `ecmaVersion` indicates the ECMAScript version to parse. Must

     // be either 3 or 5. This

     // influences support for strict mode, the set of reserved words, and

     // support for getters and setter.

     ecmaVersion: 5,

     // Turn on `strictSemicolons` to prevent the parser from doing

     // automatic semicolon insertion.

     strictSemicolons: false,

     // When `allowTrailingCommas` is false, the parser will not allow

     // trailing commas in array and object literals.

     allowTrailingCommas: true,

     // By default, reserved words are not enforced. Enable

     // `forbidReserved` to enforce them.

     forbidReserved: false,

     // When `locations` is on, `loc` properties holding objects with

     // `start` and `end` properties in `{line, column}` form (with

     // line being 1-based and column 0-based) will be attached to the

     // nodes.

     locations: false,

     // A function can be passed as `onComment` option, which will

     // cause Acorn to call that function with `(block, text, start,

     // end)` parameters whenever a comment is skipped. `block` is a

     // boolean indicating whether this is a block (`/* */`) comment,

     // `text` is the content of the comment, and `start` and `end` are

     // character offsets that denote the start and end of the comment.

     // When the `locations` option is on, two more parameters are

     // passed, the full `{line, column}` locations of the start and

     // end of the comments. Note that you are not allowed to call the

     // parser from the callback—that will corrupt its internal state.

     onComment: null,

     // Nodes have their start and end characters offsets recorded in

     // `start` and `end` properties (directly on the node, rather than

     // the `loc` object, which holds line/column data. To also add a

     // [semi-standardized][range] `range` property holding a `[start,

     // end]` array with the same numbers, set the `ranges` option to

     // `true`.

     //

     // [range]: https://bugzilla.mozilla.org/show_bug.cgi?id=745678

     ranges: false,

     // It is possible to parse multiple files into a single AST by

     // passing the tree produced by parsing the first file as

     // `program` option in subsequent parses. This will add the

     // toplevel forms of the parsed file to the `Program` (top) node

     // of an existing parse tree.

     program: null,

     // When `locations` is on, you can pass this to record the source

     // file in every node's `loc` object.

     sourceFile: null,

     // This value, if given, is stored in every node, whether

     // `locations` is on or off.

     directSourceFile: null

   };

   function setOptions(opts) {

     options = opts || {};

     for (var opt in defaultOptions) if (!Object.prototype.hasOwnProperty.call(options, opt))

       options[opt] = defaultOptions[opt];

     sourceFile = options.sourceFile || null;

   }

   // The `getLineInfo` function is mostly useful when the

   // `locations` option is off (for performance reasons) and you

   // want to find the line/column position for a given character

   // offset. `input` should be the code string that the offset refers

   // into.

   var getLineInfo = exports.getLineInfo = function(input, offset) {

     for (var line = 1, cur = 0;;) {

       lineBreak.lastIndex = cur;

       var match = lineBreak.exec(input);

       if (match && match.index < offset) {

         ++line;

         cur = match.index + match[0].length;

       } else break;

     }

     return {line: line, column: offset - cur};

   };

   // Acorn is organized as a tokenizer and a recursive-descent parser.

   // The `tokenize` export provides an interface to the tokenizer.

   // Because the tokenizer is optimized for being efficiently used by

   // the Acorn parser itself, this interface is somewhat crude and not

   // very modular. Performing another parse or call to `tokenize` will

   // reset the internal state, and invalidate existing tokenizers.

   exports.tokenize = function(inpt, opts) {

     input = String(inpt); inputLen = input.length;

     setOptions(opts);

     initTokenState();

     var t = {};

     function getToken(forceRegexp) {

       lastEnd = tokEnd;

       readToken(forceRegexp);

       t.start = tokStart; t.end = tokEnd;

       t.startLoc = tokStartLoc; t.endLoc = tokEndLoc;

       t.type = tokType; t.value = tokVal;

       return t;

     }

     getToken.jumpTo = function(pos, reAllowed) {

       tokPos = pos;

       if (options.locations) {

         tokCurLine = 1;

         tokLineStart = lineBreak.lastIndex = 0;

         var match;

         while ((match = lineBreak.exec(input)) && match.index < pos) {

           ++tokCurLine;

           tokLineStart = match.index + match[0].length;

         }

       }

       tokRegexpAllowed = reAllowed;

       skipSpace();

     };

     return getToken;

   };

   // State is kept in (closure-)global variables. We already saw the

   // `options`, `input`, and `inputLen` variables above.

   // The current position of the tokenizer in the input.

   var tokPos;

   // The start and end offsets of the current token.

   var tokStart, tokEnd;

   // When `options.locations` is true, these hold objects

   // containing the tokens start and end line/column pairs.

   var tokStartLoc, tokEndLoc;

   // The type and value of the current token. Token types are objects,

   // named by variables against which they can be compared, and

   // holding properties that describe them (indicating, for example,

   // the precedence of an infix operator, and the original name of a

   // keyword token). The kind of value that's held in `tokVal` depends

   // on the type of the token. For literals, it is the literal value,

   // for operators, the operator name, and so on.

   var tokType, tokVal;

   // Interal state for the tokenizer. To distinguish between division

   // operators and regular expressions, it remembers whether the last

   // token was one that is allowed to be followed by an expression.

   // (If it is, a slash is probably a regexp, if it isn't it's a

   // division operator. See the `parseStatement` function for a

   // caveat.)

   var tokRegexpAllowed;

   // When `options.locations` is true, these are used to keep

   // track of the current line, and know when a new line has been

   // entered.

   var tokCurLine, tokLineStart;

   // These store the position of the previous token, which is useful

   // when finishing a node and assigning its `end` position.

   var lastStart, lastEnd, lastEndLoc;

   // This is the parser's state. `inFunction` is used to reject

   // `return` statements outside of functions, `labels` to verify that

   // `break` and `continue` have somewhere to jump to, and `strict`

   // indicates whether strict mode is on.

   var inFunction, labels, strict;

   // This function is used to raise exceptions on parse errors. It

   // takes an offset integer (into the current `input`) to indicate

   // the location of the error, attaches the position to the end

   // of the error message, and then raises a `SyntaxError` with that

   // message.

   function raise(pos, message) {

     var loc = getLineInfo(input, pos);

     message += " (" + loc.line + ":" + loc.column + ")";

     var err = new SyntaxError(message);

     err.pos = pos; err.loc = loc; err.raisedAt = tokPos;

     throw err;

   }

   // Reused empty array added for node fields that are always empty.

   var empty = [];

   // ## Token types

   // The assignment of fine-grained, information-carrying type objects

   // allows the tokenizer to store the information it has about a

   // token in a way that is very cheap for the parser to look up.

   // All token type variables start with an underscore, to make them

   // easy to recognize.

   // These are the general types. The `type` property is only used to

   // make them recognizeable when debugging.

   var _num = {type: "num"}, _regexp = {type: "regexp"}, _string = {type: "string"};

   var _name = {type: "name"}, _eof = {type: "eof"};

   // Keyword tokens. The `keyword` property (also used in keyword-like

   // operators) indicates that the token originated from an

   // identifier-like word, which is used when parsing property names.

   //

   // The `beforeExpr` property is used to disambiguate between regular

   // expressions and divisions. It is set on all token types that can

   // be followed by an expression (thus, a slash after them would be a

   // regular expression).

   //

   // `isLoop` marks a keyword as starting a loop, which is important

   // to know when parsing a label, in order to allow or disallow

   // continue jumps to that label.

   var _break = {keyword: "break"}, _case = {keyword: "case", beforeExpr: true}, _catch = {keyword: "catch"};

   var _continue = {keyword: "continue"}, _debugger = {keyword: "debugger"}, _default = {keyword: "default"};

   var _do = {keyword: "do", isLoop: true}, _else = {keyword: "else", beforeExpr: true};

   var _finally = {keyword: "finally"}, _for = {keyword: "for", isLoop: true}, _function = {keyword: "function"};

   var _if = {keyword: "if"}, _return = {keyword: "return", beforeExpr: true}, _switch = {keyword: "switch"};

   var _throw = {keyword: "throw", beforeExpr: true}, _try = {keyword: "try"}, _var = {keyword: "var"};

   var _while = {keyword: "while", isLoop: true}, _with = {keyword: "with"}, _new = {keyword: "new", beforeExpr: true};

   var _this = {keyword: "this"};

   // The keywords that denote values.

   var _null = {keyword: "null", atomValue: null}, _true = {keyword: "true", atomValue: true};

   var _false = {keyword: "false", atomValue: false};

   // Some keywords are treated as regular operators. `in` sometimes

   // (when parsing `for`) needs to be tested against specifically, so

   // we assign a variable name to it for quick comparing.

   var _in = {keyword: "in", binop: 7, beforeExpr: true};

   // Map keyword names to token types.

   var keywordTypes = {"break": _break, "case": _case, "catch": _catch,

                       "continue": _continue, "debugger": _debugger, "default": _default,

                       "do": _do, "else": _else, "finally": _finally, "for": _for,

                       "function": _function, "if": _if, "return": _return, "switch": _switch,

                       "throw": _throw, "try": _try, "var": _var, "while": _while, "with": _with,

                       "null": _null, "true": _true, "false": _false, "new": _new, "in": _in,

                       "instanceof": {keyword: "instanceof", binop: 7, beforeExpr: true}, "this": _this,

                       "typeof": {keyword: "typeof", prefix: true, beforeExpr: true},

                       "void": {keyword: "void", prefix: true, beforeExpr: true},

                       "delete": {keyword: "delete", prefix: true, beforeExpr: true}};

   // Punctuation token types. Again, the `type` property is purely for debugging.

   var _bracketL = {type: "[", beforeExpr: true}, _bracketR = {type: "]"}, _braceL = {type: "{", beforeExpr: true};

   var _braceR = {type: "}"}, _parenL = {type: "(", beforeExpr: true}, _parenR = {type: ")"};

   var _comma = {type: ",", beforeExpr: true}, _semi = {type: ";", beforeExpr: true};

   var _colon = {type: ":", beforeExpr: true}, _dot = {type: "."}, _question = {type: "?", beforeExpr: true};

   // Operators. These carry several kinds of properties to help the

   // parser use them properly (the presence of these properties is

   // what categorizes them as operators).

   //

   // `binop`, when present, specifies that this operator is a binary

   // operator, and will refer to its precedence.

   //

   // `prefix` and `postfix` mark the operator as a prefix or postfix

   // unary operator. `isUpdate` specifies that the node produced by

   // the operator should be of type UpdateExpression rather than

   // simply UnaryExpression (`++` and `--`).

   //

   // `isAssign` marks all of `=`, `+=`, `-=` etcetera, which act as

   // binary operators with a very low precedence, that should result

   // in AssignmentExpression nodes.

   var _slash = {binop: 10, beforeExpr: true}, _eq = {isAssign: true, beforeExpr: true};

   var _assign = {isAssign: true, beforeExpr: true};

   var _incDec = {postfix: true, prefix: true, isUpdate: true}, _prefix = {prefix: true, beforeExpr: true};

   var _logicalOR = {binop: 1, beforeExpr: true};

   var _logicalAND = {binop: 2, beforeExpr: true};

   var _bitwiseOR = {binop: 3, beforeExpr: true};

   var _bitwiseXOR = {binop: 4, beforeExpr: true};

   var _bitwiseAND = {binop: 5, beforeExpr: true};

   var _equality = {binop: 6, beforeExpr: true};

   var _relational = {binop: 7, beforeExpr: true};

   var _bitShift = {binop: 8, beforeExpr: true};

   var _plusMin = {binop: 9, prefix: true, beforeExpr: true};

   var _multiplyModulo = {binop: 10, beforeExpr: true};

   // Provide access to the token types for external users of the

   // tokenizer.

   exports.tokTypes = {bracketL: _bracketL, bracketR: _bracketR, braceL: _braceL, braceR: _braceR,

                       parenL: _parenL, parenR: _parenR, comma: _comma, semi: _semi, colon: _colon,

                       dot: _dot, question: _question, slash: _slash, eq: _eq, name: _name, eof: _eof,

                       num: _num, regexp: _regexp, string: _string};

   for (var kw in keywordTypes) exports.tokTypes["_" + kw] = keywordTypes[kw];

   // This is a trick taken from Esprima. It turns out that, on

   // non-Chrome browsers, to check whether a string is in a set, a

   // predicate containing a big ugly `switch` statement is faster than

   // a regular expression, and on Chrome the two are about on par.

   // This function uses `eval` (non-lexical) to produce such a

   // predicate from a space-separated string of words.

   //

   // It starts by sorting the words by length.

   function makePredicate(words) {

     words = words.split(" ");

     var f = "", cats = [];

     out: for (var i = 0; i < words.length; ++i) {

       for (var j = 0; j < cats.length; ++j)

         if (cats[j][0].length == words[i].length) {

           cats[j].push(words[i]);

           continue out;

         }

       cats.push([words[i]]);

     }

     function compareTo(arr) {

       if (arr.length == 1) return f += "return str === " + JSON.stringify(arr[0]) + ";";

       f += "switch(str){";

       for (var i = 0; i < arr.length; ++i) f += "case " + JSON.stringify(arr[i]) + ":";

       f += "return true}return false;";

     }

     // When there are more than three length categories, an outer

     // switch first dispatches on the lengths, to save on comparisons.

     if (cats.length > 3) {

       cats.sort(function(a, b) {return b.length - a.length;});

       f += "switch(str.length){";

       for (var i = 0; i < cats.length; ++i) {

         var cat = cats[i];

         f += "case " + cat[0].length + ":";

         compareTo(cat);

       }

       f += "}";

     // Otherwise, simply generate a flat `switch` statement.

     } else {

       compareTo(words);

     }

     return new Function("str", f);

   }

   // The ECMAScript 3 reserved word list.

   var isReservedWord3 = makePredicate("abstract boolean byte char class double enum export extends final float goto implements import int interface long native package private protected public short static super synchronized throws transient volatile");

   // ECMAScript 5 reserved words.

   var isReservedWord5 = makePredicate("class enum extends super const export import");

   // The additional reserved words in strict mode.

   var isStrictReservedWord = makePredicate("implements interface let package private protected public static yield");

   // The forbidden variable names in strict mode.

   var isStrictBadIdWord = makePredicate("eval arguments");

   // And the keywords.

   var isKeyword = makePredicate("break case catch continue debugger default do else finally for function if return switch throw try var while with null true false instanceof typeof void delete new in this");

   // ## Character categories

   // Big ugly regular expressions that match characters in the

   // whitespace, identifier, and identifier-start categories. These

   // are only applied when a character is found to actually have a

   // code point above 128.

   var nonASCIIwhitespace = /[\u1680\u180e\u2000-\u200a\u202f\u205f\u3000\ufeff]/;

   var nonASCIIidentifierStartChars = "\xaa\xb5\xba\xc0-\xd6\xd8-\xf6\xf8-\u02c1\u02c6-\u02d1\u02e0-\u02e4\u02ec\u02ee\u0370-\u0374\u0376\u0377\u037a-\u037d\u0386\u0388-\u038a\u038c\u038e-\u03a1\u03a3-\u03f5\u03f7-\u0481\u048a-\u0527\u0531-\u0556\u0559\u0561-\u0587\u05d0-\u05ea\u05f0-\u05f2\u0620-\u064a\u066e\u066f\u0671-\u06d3\u06d5\u06e5\u06e6\u06ee\u06ef\u06fa-\u06fc\u06ff\u0710\u0712-\u072f\u074d-\u07a5\u07b1\u07ca-\u07ea\u07f4\u07f5\u07fa\u0800-\u0815\u081a\u0824\u0828\u0840-\u0858\u08a0\u08a2-\u08ac\u0904-\u0939\u093d\u0950\u0958-\u0961\u0971-\u0977\u0979-\u097f\u0985-\u098c\u098f\u0990\u0993-\u09a8\u09aa-\u09b0\u09b2\u09b6-\u09b9\u09bd\u09ce\u09dc\u09dd\u09df-\u09e1\u09f0\u09f1\u0a05-\u0a0a\u0a0f\u0a10\u0a13-\u0a28\u0a2a-\u0a30\u0a32\u0a33\u0a35\u0a36\u0a38\u0a39\u0a59-\u0a5c\u0a5e\u0a72-\u0a74\u0a85-\u0a8d\u0a8f-\u0a91\u0a93-\u0aa8\u0aaa-\u0ab0\u0ab2\u0ab3\u0ab5-\u0ab9\u0abd\u0ad0\u0ae0\u0ae1\u0b05-\u0b0c\u0b0f\u0b10\u0b13-\u0b28\u0b2a-\u0b30\u0b32\u0b33\u0b35-\u0b39\u0b3d\u0b5c\u0b5d\u0b5f-\u0b61\u0b71\u0b83\u0b85-\u0b8a\u0b8e-\u0b90\u0b92-\u0b95\u0b99\u0b9a\u0b9c\u0b9e\u0b9f\u0ba3\u0ba4\u0ba8-\u0baa\u0bae-\u0bb9\u0bd0\u0c05-\u0c0c\u0c0e-\u0c10\u0c12-\u0c28\u0c2a-\u0c33\u0c35-\u0c39\u0c3d\u0c58\u0c59\u0c60\u0c61\u0c85-\u0c8c\u0c8e-\u0c90\u0c92-\u0ca8\u0caa-\u0cb3\u0cb5-\u0cb9\u0cbd\u0cde\u0ce0\u0ce1\u0cf1\u0cf2\u0d05-\u0d0c\u0d0e-\u0d10\u0d12-\u0d3a\u0d3d\u0d4e\u0d60\u0d61\u0d7a-\u0d7f\u0d85-\u0d96\u0d9a-\u0db1\u0db3-\u0dbb\u0dbd\u0dc0-\u0dc6\u0e01-\u0e30\u0e32\u0e33\u0e40-\u0e46\u0e81\u0e82\u0e84\u0e87\u0e88\u0e8a\u0e8d\u0e94-\u0e97\u0e99-\u0e9f\u0ea1-\u0ea3\u0ea5\u0ea7\u0eaa\u0eab\u0ead-\u0eb0\u0eb2\u0eb3\u0ebd\u0ec0-\u0ec4\u0ec6\u0edc-\u0edf\u0f00\u0f40-\u0f47\u0f49-\u0f6c\u0f88-\u0f8c\u1000-\u102a\u103f\u1050-\u1055\u105a-\u105d\u1061\u1065\u1066\u106e-\u1070\u1075-\u1081\u108e\u10a0-\u10c5\u10c7\u10cd\u10d0-\u10fa\u10fc-\u1248\u124a-\u124d\u1250-\u1256\u1258\u125a-\u125d\u1260-\u1288\u128a-\u128d\u1290-\u12b0\u12b2-\u12b5\u12b8-\u12be\u12c0\u12c2-\u12c5\u12c8-\u12d6\u12d8-\u1310\u1312-\u1315\u1318-\u135a\u1380-\u138f\u13a0-\u13f4\u1401-\u166c\u166f-\u167f\u1681-\u169a\u16a0-\u16ea\u16ee-\u16f0\u1700-\u170c\u170e-\u1711\u1720-\u1731\u1740-\u1751\u1760-\u176c\u176e-\u1770\u1780-\u17b3\u17d7\u17dc\u1820-\u1877\u1880-\u18a8\u18aa\u18b0-\u18f5\u1900-\u191c\u1950-\u196d\u1970-\u1974\u1980-\u19ab\u19c1-\u19c7\u1a00-\u1a16\u1a20-\u1a54\u1aa7\u1b05-\u1b33\u1b45-\u1b4b\u1b83-\u1ba0\u1bae\u1baf\u1bba-\u1be5\u1c00-\u1c23\u1c4d-\u1c4f\u1c5a-\u1c7d\u1ce9-\u1cec\u1cee-\u1cf1\u1cf5\u1cf6\u1d00-\u1dbf\u1e00-\u1f15\u1f18-\u1f1d\u1f20-\u1f45\u1f48-\u1f4d\u1f50-\u1f57\u1f59\u1f5b\u1f5d\u1f5f-\u1f7d\u1f80-\u1fb4\u1fb6-\u1fbc\u1fbe\u1fc2-\u1fc4\u1fc6-\u1fcc\u1fd0-\u1fd3\u1fd6-\u1fdb\u1fe0-\u1fec\u1ff2-\u1ff4\u1ff6-\u1ffc\u2071\u207f\u2090-\u209c\u2102\u2107\u210a-\u2113\u2115\u2119-\u211d\u2124\u2126\u2128\u212a-\u212d\u212f-\u2139\u213c-\u213f\u2145-\u2149\u214e\u2160-\u2188\u2c00-\u2c2e\u2c30-\u2c5e\u2c60-\u2ce4\u2ceb-\u2cee\u2cf2\u2cf3\u2d00-\u2d25\u2d27\u2d2d\u2d30-\u2d67\u2d6f\u2d80-\u2d96\u2da0-\u2da6\u2da8-\u2dae\u2db0-\u2db6\u2db8-\u2dbe\u2dc0-\u2dc6\u2dc8-\u2dce\u2dd0-\u2dd6\u2dd8-\u2dde\u2e2f\u3005-\u3007\u3021-\u3029\u3031-\u3035\u3038-\u303c\u3041-\u3096\u309d-\u309f\u30a1-\u30fa\u30fc-\u30ff\u3105-\u312d\u3131-\u318e\u31a0-\u31ba\u31f0-\u31ff\u3400-\u4db5\u4e00-\u9fcc\ua000-\ua48c\ua4d0-\ua4fd\ua500-\ua60c\ua610-\ua61f\ua62a\ua62b\ua640-\ua66e\ua67f-\ua697\ua6a0-\ua6ef\ua717-\ua71f\ua722-\ua788\ua78b-\ua78e\ua790-\ua793\ua7a0-\ua7aa\ua7f8-\ua801\ua803-\ua805\ua807-\ua80a\ua80c-\ua822\ua840-\ua873\ua882-\ua8b3\ua8f2-\ua8f7\ua8fb\ua90a-\ua925\ua930-\ua946\ua960-\ua97c\ua984-\ua9b2\ua9cf\uaa00-\uaa28\uaa40-\uaa42\uaa44-\uaa4b\uaa60-\uaa76\uaa7a\uaa80-\uaaaf\uaab1\uaab5\uaab6\uaab9-\uaabd\uaac0\uaac2\uaadb-\uaadd\uaae0-\uaaea\uaaf2-\uaaf4\uab01-\uab06\uab09-\uab0e\uab11-\uab16\uab20-\uab26\uab28-\uab2e\uabc0-\uabe2\uac00-\ud7a3\ud7b0-\ud7c6\ud7cb-\ud7fb\uf900-\ufa6d\ufa70-\ufad9\ufb00-\ufb06\ufb13-\ufb17\ufb1d\ufb1f-\ufb28\ufb2a-\ufb36\ufb38-\ufb3c\ufb3e\ufb40\ufb41\ufb43\ufb44\ufb46-\ufbb1\ufbd3-\ufd3d\ufd50-\ufd8f\ufd92-\ufdc7\ufdf0-\ufdfb\ufe70-\ufe74\ufe76-\ufefc\uff21-\uff3a\uff41-\uff5a\uff66-\uffbe\uffc2-\uffc7\uffca-\uffcf\uffd2-\uffd7\uffda-\uffdc";

   var nonASCIIidentifierChars = "\u0300-\u036f\u0483-\u0487\u0591-\u05bd\u05bf\u05c1\u05c2\u05c4\u05c5\u05c7\u0610-\u061a\u0620-\u0649\u0672-\u06d3\u06e7-\u06e8\u06fb-\u06fc\u0730-\u074a\u0800-\u0814\u081b-\u0823\u0825-\u0827\u0829-\u082d\u0840-\u0857\u08e4-\u08fe\u0900-\u0903\u093a-\u093c\u093e-\u094f\u0951-\u0957\u0962-\u0963\u0966-\u096f\u0981-\u0983\u09bc\u09be-\u09c4\u09c7\u09c8\u09d7\u09df-\u09e0\u0a01-\u0a03\u0a3c\u0a3e-\u0a42\u0a47\u0a48\u0a4b-\u0a4d\u0a51\u0a66-\u0a71\u0a75\u0a81-\u0a83\u0abc\u0abe-\u0ac5\u0ac7-\u0ac9\u0acb-\u0acd\u0ae2-\u0ae3\u0ae6-\u0aef\u0b01-\u0b03\u0b3c\u0b3e-\u0b44\u0b47\u0b48\u0b4b-\u0b4d\u0b56\u0b57\u0b5f-\u0b60\u0b66-\u0b6f\u0b82\u0bbe-\u0bc2\u0bc6-\u0bc8\u0bca-\u0bcd\u0bd7\u0be6-\u0bef\u0c01-\u0c03\u0c46-\u0c48\u0c4a-\u0c4d\u0c55\u0c56\u0c62-\u0c63\u0c66-\u0c6f\u0c82\u0c83\u0cbc\u0cbe-\u0cc4\u0cc6-\u0cc8\u0cca-\u0ccd\u0cd5\u0cd6\u0ce2-\u0ce3\u0ce6-\u0cef\u0d02\u0d03\u0d46-\u0d48\u0d57\u0d62-\u0d63\u0d66-\u0d6f\u0d82\u0d83\u0dca\u0dcf-\u0dd4\u0dd6\u0dd8-\u0ddf\u0df2\u0df3\u0e34-\u0e3a\u0e40-\u0e45\u0e50-\u0e59\u0eb4-\u0eb9\u0ec8-\u0ecd\u0ed0-\u0ed9\u0f18\u0f19\u0f20-\u0f29\u0f35\u0f37\u0f39\u0f41-\u0f47\u0f71-\u0f84\u0f86-\u0f87\u0f8d-\u0f97\u0f99-\u0fbc\u0fc6\u1000-\u1029\u1040-\u1049\u1067-\u106d\u1071-\u1074\u1082-\u108d\u108f-\u109d\u135d-\u135f\u170e-\u1710\u1720-\u1730\u1740-\u1750\u1772\u1773\u1780-\u17b2\u17dd\u17e0-\u17e9\u180b-\u180d\u1810-\u1819\u1920-\u192b\u1930-\u193b\u1951-\u196d\u19b0-\u19c0\u19c8-\u19c9\u19d0-\u19d9\u1a00-\u1a15\u1a20-\u1a53\u1a60-\u1a7c\u1a7f-\u1a89\u1a90-\u1a99\u1b46-\u1b4b\u1b50-\u1b59\u1b6b-\u1b73\u1bb0-\u1bb9\u1be6-\u1bf3\u1c00-\u1c22\u1c40-\u1c49\u1c5b-\u1c7d\u1cd0-\u1cd2\u1d00-\u1dbe\u1e01-\u1f15\u200c\u200d\u203f\u2040\u2054\u20d0-\u20dc\u20e1\u20e5-\u20f0\u2d81-\u2d96\u2de0-\u2dff\u3021-\u3028\u3099\u309a\ua640-\ua66d\ua674-\ua67d\ua69f\ua6f0-\ua6f1\ua7f8-\ua800\ua806\ua80b\ua823-\ua827\ua880-\ua881\ua8b4-\ua8c4\ua8d0-\ua8d9\ua8f3-\ua8f7\ua900-\ua909\ua926-\ua92d\ua930-\ua945\ua980-\ua983\ua9b3-\ua9c0\uaa00-\uaa27\uaa40-\uaa41\uaa4c-\uaa4d\uaa50-\uaa59\uaa7b\uaae0-\uaae9\uaaf2-\uaaf3\uabc0-\uabe1\uabec\uabed\uabf0-\uabf9\ufb20-\ufb28\ufe00-\ufe0f\ufe20-\ufe26\ufe33\ufe34\ufe4d-\ufe4f\uff10-\uff19\uff3f";

   var nonASCIIidentifierStart = new RegExp("[" + nonASCIIidentifierStartChars + "]");

   var nonASCIIidentifier = new RegExp("[" + nonASCIIidentifierStartChars + nonASCIIidentifierChars + "]");

   // Whether a single character denotes a newline.

   var newline = /[\n\r\u2028\u2029]/;

   // Matches a whole line break (where CRLF is considered a single

   // line break). Used to count lines.

   var lineBreak = /\r\n|[\n\r\u2028\u2029]/g;

   // Test whether a given character code starts an identifier.

   var isIdentifierStart = exports.isIdentifierStart = function(code) {

     if (code < 65) return code === 36;

     if (code < 91) return true;

     if (code < 97) return code === 95;

     if (code < 123)return true;

     return code >= 0xaa && nonASCIIidentifierStart.test(String.fromCharCode(code));

   };

   // Test whether a given character is part of an identifier.

   var isIdentifierChar = exports.isIdentifierChar = function(code) {

     if (code < 48) return code === 36;

     if (code < 58) return true;

     if (code < 65) return false;

     if (code < 91) return true;

     if (code < 97) return code === 95;

     if (code < 123)return true;

     return code >= 0xaa && nonASCIIidentifier.test(String.fromCharCode(code));

   };

   // ## Tokenizer

   // These are used when `options.locations` is on, for the

   // `tokStartLoc` and `tokEndLoc` properties.

   function line_loc_t() {

     this.line = tokCurLine;

     this.column = tokPos - tokLineStart;

   }

   // Reset the token state. Used at the start of a parse.

   function initTokenState() {

     tokCurLine = 1;

     tokPos = tokLineStart = 0;

     tokRegexpAllowed = true;

     skipSpace();

   }

   // Called at the end of every token. Sets `tokEnd`, `tokVal`, and

   // `tokRegexpAllowed`, and skips the space after the token, so that

   // the next one's `tokStart` will point at the right position.

   function finishToken(type, val) {

     tokEnd = tokPos;

     if (options.locations) tokEndLoc = new line_loc_t;

     tokType = type;

     skipSpace();

     tokVal = val;

     tokRegexpAllowed = type.beforeExpr;

   }

   function skipBlockComment() {

     var startLoc = options.onComment && options.locations && new line_loc_t;

     var start = tokPos, end = input.indexOf("*/", tokPos += 2);

     if (end === -1) raise(tokPos - 2, "Unterminated comment");

     tokPos = end + 2;

     if (options.locations) {

       lineBreak.lastIndex = start;

       var match;

       while ((match = lineBreak.exec(input)) && match.index < tokPos) {

         ++tokCurLine;

         tokLineStart = match.index + match[0].length;

       }

     }

     if (options.onComment)

       options.onComment(true, input.slice(start + 2, end), start, tokPos,

                         startLoc, options.locations && new line_loc_t);

   }

   function skipLineComment() {

     var start = tokPos;

     var startLoc = options.onComment && options.locations && new line_loc_t;

     var ch = input.charCodeAt(tokPos+=2);

     while (tokPos < inputLen && ch !== 10 && ch !== 13 && ch !== 8232 && ch !== 8233) {

       ++tokPos;

       ch = input.charCodeAt(tokPos);

     }

     if (options.onComment)

       options.onComment(false, input.slice(start + 2, tokPos), start, tokPos,

                         startLoc, options.locations && new line_loc_t);

   }

   // Called at the start of the parse and after every token. Skips

   // whitespace and comments, and.

   function skipSpace() {

     while (tokPos < inputLen) {

       var ch = input.charCodeAt(tokPos);

       if (ch === 32) { // ' '

         ++tokPos;

       } else if (ch === 13) {

         ++tokPos;

         var next = input.charCodeAt(tokPos);

         if (next === 10) {

           ++tokPos;

         }

         if (options.locations) {

           ++tokCurLine;

           tokLineStart = tokPos;

         }

       } else if (ch === 10 || ch === 8232 || ch === 8233) {

         ++tokPos;

         if (options.locations) {

           ++tokCurLine;

           tokLineStart = tokPos;

         }

       } else if (ch > 8 && ch < 14) {

         ++tokPos;

       } else if (ch === 47) { // '/'

         var next = input.charCodeAt(tokPos + 1);

         if (next === 42) { // '*'

           skipBlockComment();

         } else if (next === 47) { // '/'

           skipLineComment();

         } else break;

       } else if (ch === 160) { // '\xa0'

         ++tokPos;

       } else if (ch >= 5760 && nonASCIIwhitespace.test(String.fromCharCode(ch))) {

         ++tokPos;

       } else {

         break;

       }

     }

   }

   // ### Token reading

   // This is the function that is called to fetch the next token. It

   // is somewhat obscure, because it works in character codes rather

   // than characters, and because operator parsing has been inlined

   // into it.

   //

   // All in the name of speed.

   //

   // The `forceRegexp` parameter is used in the one case where the

   // `tokRegexpAllowed` trick does not work. See `parseStatement`.

   function readToken_dot() {

     var next = input.charCodeAt(tokPos + 1);

     if (next >= 48 && next <= 57) return readNumber(true);

     ++tokPos;

     return finishToken(_dot);

   }

   function readToken_slash() { // '/'

     var next = input.charCodeAt(tokPos + 1);

     if (tokRegexpAllowed) {++tokPos; return readRegexp();}

     if (next === 61) return finishOp(_assign, 2);

     return finishOp(_slash, 1);

   }

   function readToken_mult_modulo() { // '%*'

     var next = input.charCodeAt(tokPos + 1);

     if (next === 61) return finishOp(_assign, 2);

     return finishOp(_multiplyModulo, 1);

   }

   function readToken_pipe_amp(code) { // '|&'

     var next = input.charCodeAt(tokPos + 1);

     if (next === code) return finishOp(code === 124 ? _logicalOR : _logicalAND, 2);

     if (next === 61) return finishOp(_assign, 2);

     return finishOp(code === 124 ? _bitwiseOR : _bitwiseAND, 1);

   }

   function readToken_caret() { // '^'

     var next = input.charCodeAt(tokPos + 1);

     if (next === 61) return finishOp(_assign, 2);

     return finishOp(_bitwiseXOR, 1);

   }

   function readToken_plus_min(code) { // '+-'

     var next = input.charCodeAt(tokPos + 1);

     if (next === code) {

       if (next == 45 && input.charCodeAt(tokPos + 2) == 62 &&

           newline.test(input.slice(lastEnd, tokPos))) {

         // A `-->` line comment

         tokPos += 3;

         skipLineComment();

         skipSpace();

         return readToken();

       }

       return finishOp(_incDec, 2);

     }

     if (next === 61) return finishOp(_assign, 2);

     return finishOp(_plusMin, 1);

   }

   function readToken_lt_gt(code) { // '<>'

     var next = input.charCodeAt(tokPos + 1);

     var size = 1;

     if (next === code) {

       size = code === 62 && input.charCodeAt(tokPos + 2) === 62 ? 3 : 2;

       if (input.charCodeAt(tokPos + size) === 61) return finishOp(_assign, size + 1);

       return finishOp(_bitShift, size);

     }

     if (next == 33 && code == 60 && input.charCodeAt(tokPos + 2) == 45 &&

         input.charCodeAt(tokPos + 3) == 45) {

       // `<!--`, an XML-style comment that should be interpreted as a line comment

       tokPos += 4;

       skipLineComment();

       skipSpace();

       return readToken();

     }

     if (next === 61)

       size = input.charCodeAt(tokPos + 2) === 61 ? 3 : 2;

     return finishOp(_relational, size);

   }

   function readToken_eq_excl(code) { // '=!'

     var next = input.charCodeAt(tokPos + 1);

     if (next === 61) return finishOp(_equality, input.charCodeAt(tokPos + 2) === 61 ? 3 : 2);

     return finishOp(code === 61 ? _eq : _prefix, 1);

   }

   function getTokenFromCode(code) {

     switch(code) {

       // The interpretation of a dot depends on whether it is followed

       // by a digit.

     case 46: // '.'

       return readToken_dot();

       // Punctuation tokens.

     case 40: ++tokPos; return finishToken(_parenL);

     case 41: ++tokPos; return finishToken(_parenR);

     case 59: ++tokPos; return finishToken(_semi);

     case 44: ++tokPos; return finishToken(_comma);

     case 91: ++tokPos; return finishToken(_bracketL);

     case 93: ++tokPos; return finishToken(_bracketR);

     case 123: ++tokPos; return finishToken(_braceL);

     case 125: ++tokPos; return finishToken(_braceR);

     case 58: ++tokPos; return finishToken(_colon);

     case 63: ++tokPos; return finishToken(_question);

       // '0x' is a hexadecimal number.

     case 48: // '0'

       var next = input.charCodeAt(tokPos + 1);

       if (next === 120 || next === 88) return readHexNumber();

       // Anything else beginning with a digit is an integer, octal

       // number, or float.

     case 49: case 50: case 51: case 52: case 53: case 54: case 55: case 56: case 57: // 1-9

       return readNumber(false);

       // Quotes produce strings.

     case 34: case 39: // '"', "'"

       return readString(code);

     // Operators are parsed inline in tiny state machines. '=' (61) is

     // often referred to. `finishOp` simply skips the amount of

     // characters it is given as second argument, and returns a token

     // of the type given by its first argument.

     case 47: // '/'

       return readToken_slash(code);

     case 37: case 42: // '%*'

       return readToken_mult_modulo();

     case 124: case 38: // '|&'

       return readToken_pipe_amp(code);

     case 94: // '^'

       return readToken_caret();

     case 43: case 45: // '+-'

       return readToken_plus_min(code);

     case 60: case 62: // '<>'

       return readToken_lt_gt(code);

     case 61: case 33: // '=!'

       return readToken_eq_excl(code);

     case 126: // '~'

       return finishOp(_prefix, 1);

     }

     return false;

   }

   function readToken(forceRegexp) {

     if (!forceRegexp) tokStart = tokPos;

     else tokPos = tokStart + 1;

     if (options.locations) tokStartLoc = new line_loc_t;

     if (forceRegexp) return readRegexp();

     if (tokPos >= inputLen) return finishToken(_eof);

     var code = input.charCodeAt(tokPos);

     // Identifier or keyword. '\uXXXX' sequences are allowed in

     // identifiers, so '\' also dispatches to that.

     if (isIdentifierStart(code) || code === 92 /* '\' */) return readWord();

     var tok = getTokenFromCode(code);

     if (tok === false) {

       // If we are here, we either found a non-ASCII identifier

       // character, or something that's entirely disallowed.

       var ch = String.fromCharCode(code);

       if (ch === "\\" || nonASCIIidentifierStart.test(ch)) return readWord();

       raise(tokPos, "Unexpected character '" + ch + "'");

     }

     return tok;

   }

   function finishOp(type, size) {

     var str = input.slice(tokPos, tokPos + size);

     tokPos += size;

     finishToken(type, str);

   }

   // Parse a regular expression. Some context-awareness is necessary,

   // since a '/' inside a '[]' set does not end the expression.

   function readRegexp() {

     var content = "", escaped, inClass, start = tokPos;

     for (;;) {

       if (tokPos >= inputLen) raise(start, "Unterminated regular expression");

       var ch = input.charAt(tokPos);

       if (newline.test(ch)) raise(start, "Unterminated regular expression");

       if (!escaped) {

         if (ch === "[") inClass = true;

         else if (ch === "]" && inClass) inClass = false;

         else if (ch === "/" && !inClass) break;

         escaped = ch === "\\";

       } else escaped = false;

       ++tokPos;

     }

     var content = input.slice(start, tokPos);

     ++tokPos;

     // Need to use `readWord1` because '\uXXXX' sequences are allowed

     // here (don't ask).

     var mods = readWord1();

     if (mods && !/^[gmsiy]*$/.test(mods)) raise(start, "Invalid regexp flag");

     try {

       var value = new RegExp(content, mods);

     } catch (e) {

       if (e instanceof SyntaxError) raise(start, e.message);

       raise(e);

     }

     return finishToken(_regexp, value);

   }

   // Read an integer in the given radix. Return null if zero digits

   // were read, the integer value otherwise. When `len` is given, this

   // will return `null` unless the integer has exactly `len` digits.

   function readInt(radix, len) {

     var start = tokPos, total = 0;

     for (var i = 0, e = len == null ? Infinity : len; i < e; ++i) {

       var code = input.charCodeAt(tokPos), val;

       if (code >= 97) val = code - 97 + 10; // a

       else if (code >= 65) val = code - 65 + 10; // A

       else if (code >= 48 && code <= 57) val = code - 48; // 0-9

       else val = Infinity;

       if (val >= radix) break;

       ++tokPos;

       total = total * radix + val;

     }

     if (tokPos === start || len != null && tokPos - start !== len) return null;

     return total;

   }

   function readHexNumber() {

     tokPos += 2; // 0x

     var val = readInt(16);

     if (val == null) raise(tokStart + 2, "Expected hexadecimal number");

     if (isIdentifierStart(input.charCodeAt(tokPos))) raise(tokPos, "Identifier directly after number");

     return finishToken(_num, val);

   }

   // Read an integer, octal integer, or floating-point number.

   function readNumber(startsWithDot) {

     var start = tokPos, isFloat = false, octal = input.charCodeAt(tokPos) === 48;

     if (!startsWithDot && readInt(10) === null) raise(start, "Invalid number");

     if (input.charCodeAt(tokPos) === 46) {

       ++tokPos;

       readInt(10);

       isFloat = true;

     }

     var next = input.charCodeAt(tokPos);

     if (next === 69 || next === 101) { // 'eE'

       next = input.charCodeAt(++tokPos);

       if (next === 43 || next === 45) ++tokPos; // '+-'

       if (readInt(10) === null) raise(start, "Invalid number");

       isFloat = true;

     }

     if (isIdentifierStart(input.charCodeAt(tokPos))) raise(tokPos, "Identifier directly after number");

     var str = input.slice(start, tokPos), val;

     if (isFloat) val = parseFloat(str);

     else if (!octal || str.length === 1) val = parseInt(str, 10);

     else if (/[89]/.test(str) || strict) raise(start, "Invalid number");

     else val = parseInt(str, 8);

     return finishToken(_num, val);

   }

   // Read a string value, interpreting backslash-escapes.

   function readString(quote) {

     tokPos++;

     var out = "";

     for (;;) {

       if (tokPos >= inputLen) raise(tokStart, "Unterminated string constant");

       var ch = input.charCodeAt(tokPos);

       if (ch === quote) {

         ++tokPos;

         return finishToken(_string, out);

       }

       if (ch === 92) { // '\'

         ch = input.charCodeAt(++tokPos);

         var octal = /^[0-7]+/.exec(input.slice(tokPos, tokPos + 3));

         if (octal) octal = octal[0];

         while (octal && parseInt(octal, 8) > 255) octal = octal.slice(0, -1);

         if (octal === "0") octal = null;

         ++tokPos;

         if (octal) {

           if (strict) raise(tokPos - 2, "Octal literal in strict mode");

           out += String.fromCharCode(parseInt(octal, 8));

           tokPos += octal.length - 1;

         } else {

           switch (ch) {

           case 110: out += "\n"; break; // 'n' -> '\n'

           case 114: out += "\r"; break; // 'r' -> '\r'

           case 120: out += String.fromCharCode(readHexChar(2)); break; // 'x'

           case 117: out += String.fromCharCode(readHexChar(4)); break; // 'u'

           case 85: out += String.fromCharCode(readHexChar(8)); break; // 'U'

           case 116: out += "\t"; break; // 't' -> '\t'

           case 98: out += "\b"; break; // 'b' -> '\b'

           case 118: out += "\u000b"; break; // 'v' -> '\u000b'

           case 102: out += "\f"; break; // 'f' -> '\f'

           case 48: out += "\0"; break; // 0 -> '\0'

           case 13: if (input.charCodeAt(tokPos) === 10) ++tokPos; // '\r\n'

           case 10: // ' \n'

             if (options.locations) { tokLineStart = tokPos; ++tokCurLine; }

             break;

           default: out += String.fromCharCode(ch); break;

           }

         }

       } else {

         if (ch === 13 || ch === 10 || ch === 8232 || ch === 8233) raise(tokStart, "Unterminated string constant");

         out += String.fromCharCode(ch); // '\'

         ++tokPos;

       }

     }

   }

   // Used to read character escape sequences ('\x', '\u', '\U').

   function readHexChar(len) {

     var n = readInt(16, len);

     if (n === null) raise(tokStart, "Bad character escape sequence");

     return n;

   }

   // Used to signal to callers of `readWord1` whether the word

   // contained any escape sequences. This is needed because words with

   // escape sequences must not be interpreted as keywords.

   var containsEsc;

   // Read an identifier, and return it as a string. Sets `containsEsc`

   // to whether the word contained a '\u' escape.

   //

   // Only builds up the word character-by-character when it actually

   // containeds an escape, as a micro-optimization.

   function readWord1() {

     containsEsc = false;

     var word, first = true, start = tokPos;

     for (;;) {

       var ch = input.charCodeAt(tokPos);

       if (isIdentifierChar(ch)) {

         if (containsEsc) word += input.charAt(tokPos);

         ++tokPos;

       } else if (ch === 92) { // "\"

         if (!containsEsc) word = input.slice(start, tokPos);

         containsEsc = true;

         if (input.charCodeAt(++tokPos) != 117) // "u"

           raise(tokPos, "Expecting Unicode escape sequence \\uXXXX");

         ++tokPos;

         var esc = readHexChar(4);

         var escStr = String.fromCharCode(esc);

         if (!escStr) raise(tokPos - 1, "Invalid Unicode escape");

         if (!(first ? isIdentifierStart(esc) : isIdentifierChar(esc)))

           raise(tokPos - 4, "Invalid Unicode escape");

         word += escStr;

       } else {

         break;

       }

       first = false;

     }

     return containsEsc ? word : input.slice(start, tokPos);

   }

   // Read an identifier or keyword token. Will check for reserved

   // words when necessary.

   function readWord() {

     var word = readWord1();

     var type = _name;

     if (!containsEsc) {

       if (isKeyword(word)) type = keywordTypes[word];

       else if (options.forbidReserved &&

                (options.ecmaVersion === 3 ? isReservedWord3 : isReservedWord5)(word) ||

                strict && isStrictReservedWord(word))

         raise(tokStart, "The keyword '" + word + "' is reserved");

     }

     return finishToken(type, word);

   }

   // ## Parser

   // A recursive descent parser operates by defining functions for all

   // syntactic elements, and recursively calling those, each function

   // advancing the input stream and returning an AST node. Precedence

   // of constructs (for example, the fact that `!x[1]` means `!(x[1])`

   // instead of `(!x)[1]` is handled by the fact that the parser

   // function that parses unary prefix operators is called first, and

   // in turn calls the function that parses `[]` subscripts — that

   // way, it'll receive the node for `x[1]` already parsed, and wraps

   // *that* in the unary operator node.

   //

   // Acorn uses an [operator precedence parser][opp] to handle binary

   // operator precedence, because it is much more compact than using

   // the technique outlined above, which uses different, nesting

   // functions to specify precedence, for all of the ten binary

   // precedence levels that JavaScript defines.

   //

   // [opp]: http://en.wikipedia.org/wiki/Operator-precedence_parser

   // ### Parser utilities

   // Continue to the next token.

   function next() {

     lastStart = tokStart;

     lastEnd = tokEnd;

     lastEndLoc = tokEndLoc;

     readToken();

   }

   // Enter strict mode. Re-reads the next token to please pedantic

   // tests ("use strict"; 010; -- should fail).

   function setStrict(strct) {

     strict = strct;

     tokPos = tokStart;

     if (options.locations) {

       while (tokPos < tokLineStart) {

         tokLineStart = input.lastIndexOf("\n", tokLineStart - 2) + 1;

         --tokCurLine;

       }

     }

     skipSpace();

     readToken();

   }

   // Start an AST node, attaching a start offset.

   function node_t() {

     this.type = null;

     this.start = tokStart;

     this.end = null;

   }

   function node_loc_t() {

     this.start = tokStartLoc;

     this.end = null;

     if (sourceFile !== null) this.source = sourceFile;

   }

   function startNode() {

     var node = new node_t();

     if (options.locations)

       node.loc = new node_loc_t();

     if (options.directSourceFile)

       node.sourceFile = options.directSourceFile;

     if (options.ranges)

       node.range = [tokStart, 0];

     return node;

   }

   // Start a node whose start offset information should be based on

   // the start of another node. For example, a binary operator node is

   // only started after its left-hand side has already been parsed.

   function startNodeFrom(other) {

     var node = new node_t();

     node.start = other.start;

     if (options.locations) {

       node.loc = new node_loc_t();

       node.loc.start = other.loc.start;

     }

     if (options.ranges)

       node.range = [other.range[0], 0];

     return node;

   }

   // Finish an AST node, adding `type` and `end` properties.

   function finishNode(node, type) {

     node.type = type;

     node.end = lastEnd;

     if (options.locations)

       node.loc.end = lastEndLoc;

     if (options.ranges)

       node.range[1] = lastEnd;

     return node;

   }

   // Test whether a statement node is the string literal `"use strict"`.

   function isUseStrict(stmt) {

     return options.ecmaVersion >= 5 && stmt.type === "ExpressionStatement" &&

       stmt.expression.type === "Literal" && stmt.expression.value === "use strict";

   }

   // Predicate that tests whether the next token is of the given

   // type, and if yes, consumes it as a side effect.

   function eat(type) {

     if (tokType === type) {

       next();

       return true;

     }

   }

   // Test whether a semicolon can be inserted at the current position.

   function canInsertSemicolon() {

     return !options.strictSemicolons &&

       (tokType === _eof || tokType === _braceR || newline.test(input.slice(lastEnd, tokStart)));

   }

   // Consume a semicolon, or, failing that, see if we are allowed to

   // pretend that there is a semicolon at this position.

   function semicolon() {

     if (!eat(_semi) && !canInsertSemicolon()) unexpected();

   }

   // Expect a token of a given type. If found, consume it, otherwise,

   // raise an unexpected token error.

   function expect(type) {

     if (tokType === type) next();

     else unexpected();

   }

   // Raise an unexpected token error.

   function unexpected() {

     raise(tokStart, "Unexpected token");

   }

   // Verify that a node is an lval — something that can be assigned

   // to.

   function checkLVal(expr) {

     if (expr.type !== "Identifier" && expr.type !== "MemberExpression")

       raise(expr.start, "Assigning to rvalue");

     if (strict && expr.type === "Identifier" && isStrictBadIdWord(expr.name))

       raise(expr.start, "Assigning to " + expr.name + " in strict mode");

   }

   // ### Statement parsing

   // Parse a program. Initializes the parser, reads any number of

   // statements, and wraps them in a Program node.  Optionally takes a

   // `program` argument.  If present, the statements will be appended

   // to its body instead of creating a new node.

   function parseTopLevel(program) {

     lastStart = lastEnd = tokPos;

     if (options.locations) lastEndLoc = new line_loc_t;

     inFunction = strict = null;

     labels = [];

     readToken();

     var node = program || startNode(), first = true;

     if (!program) node.body = [];

     while (tokType !== _eof) {

       var stmt = parseStatement();

       node.body.push(stmt);

       if (first && isUseStrict(stmt)) setStrict(true);

       first = false;

     }

     return finishNode(node, "Program");

   }

   var loopLabel = {kind: "loop"}, switchLabel = {kind: "switch"};

   // Parse a single statement.

   //

   // If expecting a statement and finding a slash operator, parse a

   // regular expression literal. This is to handle cases like

   // `if (foo) /blah/.exec(foo);`, where looking at the previous token

   // does not help.

   function parseStatement() {

     if (tokType === _slash || tokType === _assign && tokVal == "/=")

       readToken(true);

     var starttype = tokType, node = startNode();

     // Most types of statements are recognized by the keyword they

     // start with. Many are trivial to parse, some require a bit of

     // complexity.

     switch (starttype) {

     case _break: case _continue:

       next();

       var isBreak = starttype === _break;

       if (eat(_semi) || canInsertSemicolon()) node.label = null;

       else if (tokType !== _name) unexpected();

       else {

         node.label = parseIdent();

         semicolon();

       }

       // Verify that there is an actual destination to break or

       // continue to.

       for (var i = 0; i < labels.length; ++i) {

         var lab = labels[i];

         if (node.label == null || lab.name === node.label.name) {

           if (lab.kind != null && (isBreak || lab.kind === "loop")) break;

           if (node.label && isBreak) break;

         }

       }

       if (i === labels.length) raise(node.start, "Unsyntactic " + starttype.keyword);

       return finishNode(node, isBreak ? "BreakStatement" : "ContinueStatement");

     case _debugger:

       next();

       semicolon();

       return finishNode(node, "DebuggerStatement");

     case _do:

       next();

       labels.push(loopLabel);

       node.body = parseStatement();

       labels.pop();

       expect(_while);

       node.test = parseParenExpression();

       semicolon();

       return finishNode(node, "DoWhileStatement");

       // Disambiguating between a `for` and a `for`/`in` loop is

       // non-trivial. Basically, we have to parse the init `var`

       // statement or expression, disallowing the `in` operator (see

       // the second parameter to `parseExpression`), and then check

       // whether the next token is `in`. When there is no init part

       // (semicolon immediately after the opening parenthesis), it is

       // a regular `for` loop.

     case _for:

       next();

       labels.push(loopLabel);

       expect(_parenL);

       if (tokType === _semi) return parseFor(node, null);

       if (tokType === _var) {

         var init = startNode();

         next();

         parseVar(init, true);

         finishNode(init, "VariableDeclaration");

         if (init.declarations.length === 1 && eat(_in))

           return parseForIn(node, init);

         return parseFor(node, init);

       }

       var init = parseExpression(false, true);

       if (eat(_in)) {checkLVal(init); return parseForIn(node, init);}

       return parseFor(node, init);

     case _function:

       next();

       return parseFunction(node, true);

     case _if:

       next();

       node.test = parseParenExpression();

       node.consequent = parseStatement();

       node.alternate = eat(_else) ? parseStatement() : null;

       return finishNode(node, "IfStatement");

     case _return:

       if (!inFunction) raise(tokStart, "'return' outside of function");

       next();

       // In `return` (and `break`/`continue`), the keywords with

       // optional arguments, we eagerly look for a semicolon or the

       // possibility to insert one.

       if (eat(_semi) || canInsertSemicolon()) node.argument = null;

       else { node.argument = parseExpression(); semicolon(); }

       return finishNode(node, "ReturnStatement");

     case _switch:

       next();

       node.discriminant = parseParenExpression();

       node.cases = [];

       expect(_braceL);

       labels.push(switchLabel);

       // Statements under must be grouped (by label) in SwitchCase

       // nodes. `cur` is used to keep the node that we are currently

       // adding statements to.

       for (var cur, sawDefault; tokType != _braceR;) {

         if (tokType === _case || tokType === _default) {

           var isCase = tokType === _case;

           if (cur) finishNode(cur, "SwitchCase");

           node.cases.push(cur = startNode());

           cur.consequent = [];

           next();

           if (isCase) cur.test = parseExpression();

           else {

             if (sawDefault) raise(lastStart, "Multiple default clauses"); sawDefault = true;

             cur.test = null;

           }

           expect(_colon);

         } else {

           if (!cur) unexpected();

           cur.consequent.push(parseStatement());

         }

       }

       if (cur) finishNode(cur, "SwitchCase");

       next(); // Closing brace

       labels.pop();

       return finishNode(node, "SwitchStatement");

     case _throw:

       next();

       if (newline.test(input.slice(lastEnd, tokStart)))

         raise(lastEnd, "Illegal newline after throw");

       node.argument = parseExpression();

       semicolon();

       return finishNode(node, "ThrowStatement");

     case _try:

       next();

       node.block = parseBlock();

       node.handler = null;

       if (tokType === _catch) {

         var clause = startNode();

         next();

         expect(_parenL);

         clause.param = parseIdent();

         if (strict && isStrictBadIdWord(clause.param.name))

           raise(clause.param.start, "Binding " + clause.param.name + " in strict mode");

         expect(_parenR);

         clause.guard = null;

         clause.body = parseBlock();

         node.handler = finishNode(clause, "CatchClause");

       }

       node.guardedHandlers = empty;

       node.finalizer = eat(_finally) ? parseBlock() : null;

       if (!node.handler && !node.finalizer)

         raise(node.start, "Missing catch or finally clause");

       return finishNode(node, "TryStatement");

     case _var:

       next();

       parseVar(node);

       semicolon();

       return finishNode(node, "VariableDeclaration");

     case _while:

       next();

       node.test = parseParenExpression();

       labels.push(loopLabel);

       node.body = parseStatement();

       labels.pop();

       return finishNode(node, "WhileStatement");

     case _with:

       if (strict) raise(tokStart, "'with' in strict mode");

       next();

       node.object = parseParenExpression();

       node.body = parseStatement();

       return finishNode(node, "WithStatement");

     case _braceL:

       return parseBlock();

     case _semi:

       next();

       return finishNode(node, "EmptyStatement");

       // If the statement does not start with a statement keyword or a

       // brace, it's an ExpressionStatement or LabeledStatement. We

       // simply start parsing an expression, and afterwards, if the

       // next token is a colon and the expression was a simple

       // Identifier node, we switch to interpreting it as a label.

     default:

       var maybeName = tokVal, expr = parseExpression();

       if (starttype === _name && expr.type === "Identifier" && eat(_colon)) {

         for (var i = 0; i < labels.length; ++i)

           if (labels[i].name === maybeName) raise(expr.start, "Label '" + maybeName + "' is already declared");

         var kind = tokType.isLoop ? "loop" : tokType === _switch ? "switch" : null;

         labels.push({name: maybeName, kind: kind});

         node.body = parseStatement();

         labels.pop();

         node.label = expr;

         return finishNode(node, "LabeledStatement");

       } else {

         node.expression = expr;

         semicolon();

         return finishNode(node, "ExpressionStatement");

       }

     }

   }

   // Used for constructs like `switch` and `if` that insist on

   // parentheses around their expression.

   function parseParenExpression() {

     expect(_parenL);

     var val = parseExpression();

     expect(_parenR);

     return val;

   }

   // Parse a semicolon-enclosed block of statements, handling `"use

   // strict"` declarations when `allowStrict` is true (used for

   // function bodies).

   function parseBlock(allowStrict) {

     var node = startNode(), first = true, strict = false, oldStrict;

     node.body = [];

     expect(_braceL);

     while (!eat(_braceR)) {

       var stmt = parseStatement();

       node.body.push(stmt);

       if (first && allowStrict && isUseStrict(stmt)) {

         oldStrict = strict;

         setStrict(strict = true);

       }

       first = false;

     }

     if (strict && !oldStrict) setStrict(false);

     return finishNode(node, "BlockStatement");

   }

   // Parse a regular `for` loop. The disambiguation code in

   // `parseStatement` will already have parsed the init statement or

   // expression.

   function parseFor(node, init) {

     node.init = init;

     expect(_semi);

     node.test = tokType === _semi ? null : parseExpression();

     expect(_semi);

     node.update = tokType === _parenR ? null : parseExpression();

     expect(_parenR);

     node.body = parseStatement();

     labels.pop();

     return finishNode(node, "ForStatement");

   }

   // Parse a `for`/`in` loop.

   function parseForIn(node, init) {

     node.left = init;

     node.right = parseExpression();

     expect(_parenR);

     node.body = parseStatement();

     labels.pop();

     return finishNode(node, "ForInStatement");

   }

   // Parse a list of variable declarations.

   function parseVar(node, noIn) {

     node.declarations = [];

     node.kind = "var";

     for (;;) {

       var decl = startNode();

       decl.id = parseIdent();

       if (strict && isStrictBadIdWord(decl.id.name))

         raise(decl.id.start, "Binding " + decl.id.name + " in strict mode");

       decl.init = eat(_eq) ? parseExpression(true, noIn) : null;

       node.declarations.push(finishNode(decl, "VariableDeclarator"));

       if (!eat(_comma)) break;

     }

     return node;

   }

   // ### Expression parsing

   // These nest, from the most general expression type at the top to

   // 'atomic', nondivisible expression types at the bottom. Most of

   // the functions will simply let the function(s) below them parse,

   // and, *if* the syntactic construct they handle is present, wrap

   // the AST node that the inner parser gave them in another node.

   // Parse a full expression. The arguments are used to forbid comma

   // sequences (in argument lists, array literals, or object literals)

   // or the `in` operator (in for loops initalization expressions).

   function parseExpression(noComma, noIn) {

     var expr = parseMaybeAssign(noIn);

     if (!noComma && tokType === _comma) {

       var node = startNodeFrom(expr);

       node.expressions = [expr];

       while (eat(_comma)) node.expressions.push(parseMaybeAssign(noIn));

       return finishNode(node, "SequenceExpression");

     }

     return expr;

   }

   // Parse an assignment expression. This includes applications of

   // operators like `+=`.

   function parseMaybeAssign(noIn) {

     var left = parseMaybeConditional(noIn);

     if (tokType.isAssign) {

       var node = startNodeFrom(left);

       node.operator = tokVal;

       node.left = left;

       next();

       node.right = parseMaybeAssign(noIn);

       checkLVal(left);

       return finishNode(node, "AssignmentExpression");

     }

     return left;

   }

   // Parse a ternary conditional (`?:`) operator.

   function parseMaybeConditional(noIn) {

     var expr = parseExprOps(noIn);

     if (eat(_question)) {

       var node = startNodeFrom(expr);

       node.test = expr;

       node.consequent = parseExpression(true);

       expect(_colon);

       node.alternate = parseExpression(true, noIn);

       return finishNode(node, "ConditionalExpression");

     }

     return expr;

   }

   // Start the precedence parser.

   function parseExprOps(noIn) {

     return parseExprOp(parseMaybeUnary(), -1, noIn);

   }

   // Parse binary operators with the operator precedence parsing

   // algorithm. `left` is the left-hand side of the operator.

   // `minPrec` provides context that allows the function to stop and

   // defer further parser to one of its callers when it encounters an

   // operator that has a lower precedence than the set it is parsing.

   function parseExprOp(left, minPrec, noIn) {

     var prec = tokType.binop;

     if (prec != null && (!noIn || tokType !== _in)) {

       if (prec > minPrec) {

         var node = startNodeFrom(left);

         node.left = left;

         node.operator = tokVal;

         var op = tokType;

         next();

         node.right = parseExprOp(parseMaybeUnary(), prec, noIn);

         var exprNode = finishNode(node, (op === _logicalOR || op === _logicalAND) ? "LogicalExpression" : "BinaryExpression");

         return parseExprOp(exprNode, minPrec, noIn);

       }

     }

     return left;

   }

   // Parse unary operators, both prefix and postfix.

   function parseMaybeUnary() {

     if (tokType.prefix) {

       var node = startNode(), update = tokType.isUpdate;

       node.operator = tokVal;

       node.prefix = true;

       tokRegexpAllowed = true;

       next();

       node.argument = parseMaybeUnary();

       if (update) checkLVal(node.argument);

       else if (strict && node.operator === "delete" &&

                node.argument.type === "Identifier")

         raise(node.start, "Deleting local variable in strict mode");

       return finishNode(node, update ? "UpdateExpression" : "UnaryExpression");

     }

     var expr = parseExprSubscripts();

     while (tokType.postfix && !canInsertSemicolon()) {

       var node = startNodeFrom(expr);

       node.operator = tokVal;

       node.prefix = false;

       node.argument = expr;

       checkLVal(expr);

       next();

       expr = finishNode(node, "UpdateExpression");

     }

     return expr;

   }

   // Parse call, dot, and `[]`-subscript expressions.

   function parseExprSubscripts() {

     return parseSubscripts(parseExprAtom());

   }

   function parseSubscripts(base, noCalls) {

     if (eat(_dot)) {

       var node = startNodeFrom(base);

       node.object = base;

       node.property = parseIdent(true);

       node.computed = false;

       return parseSubscripts(finishNode(node, "MemberExpression"), noCalls);

     } else if (eat(_bracketL)) {

       var node = startNodeFrom(base);

       node.object = base;

       node.property = parseExpression();

       node.computed = true;

       expect(_bracketR);

       return parseSubscripts(finishNode(node, "MemberExpression"), noCalls);

     } else if (!noCalls && eat(_parenL)) {

       var node = startNodeFrom(base);

       node.callee = base;

       node.arguments = parseExprList(_parenR, false);

       return parseSubscripts(finishNode(node, "CallExpression"), noCalls);

     } else return base;

   }

   // Parse an atomic expression — either a single token that is an

   // expression, an expression started by a keyword like `function` or

   // `new`, or an expression wrapped in punctuation like `()`, `[]`,

   // or `{}`.

   function parseExprAtom() {

     switch (tokType) {

     case _this:

       var node = startNode();

       next();

       return finishNode(node, "ThisExpression");

     case _name:

       return parseIdent();

     case _num: case _string: case _regexp:

       var node = startNode();

       node.value = tokVal;

       node.raw = input.slice(tokStart, tokEnd);

       next();

       return finishNode(node, "Literal");

     case _null: case _true: case _false:

       var node = startNode();

       node.value = tokType.atomValue;

       node.raw = tokType.keyword;

       next();

       return finishNode(node, "Literal");

     case _parenL:

       var tokStartLoc1 = tokStartLoc, tokStart1 = tokStart;

       next();

       var val = parseExpression();

       val.start = tokStart1;

       val.end = tokEnd;

       if (options.locations) {

         val.loc.start = tokStartLoc1;

         val.loc.end = tokEndLoc;

       }

       if (options.ranges)

         val.range = [tokStart1, tokEnd];

       expect(_parenR);

       return val;

     case _bracketL:

       var node = startNode();

       next();

       node.elements = parseExprList(_bracketR, true, true);

       return finishNode(node, "ArrayExpression");

     case _braceL:

       return parseObj();

     case _function:

       var node = startNode();

       next();

       return parseFunction(node, false);

     case _new:

       return parseNew();

     default:

       unexpected();

     }

   }

   // New's precedence is slightly tricky. It must allow its argument

   // to be a `[]` or dot subscript expression, but not a call — at

   // least, not without wrapping it in parentheses. Thus, it uses the

   function parseNew() {

     var node = startNode();

     next();

     node.callee = parseSubscripts(parseExprAtom(), true);

     if (eat(_parenL)) node.arguments = parseExprList(_parenR, false);

     else node.arguments = empty;

     return finishNode(node, "NewExpression");

   }

   // Parse an object literal.

   function parseObj() {

     var node = startNode(), first = true, sawGetSet = false;

     node.properties = [];

     next();

     while (!eat(_braceR)) {

       if (!first) {

         expect(_comma);

         if (options.allowTrailingCommas && eat(_braceR)) break;

       } else first = false;

       var prop = {key: parsePropertyName()}, isGetSet = false, kind;

       if (eat(_colon)) {

         prop.value = parseExpression(true);

         kind = prop.kind = "init";

       } else if (options.ecmaVersion >= 5 && prop.key.type === "Identifier" &&

                  (prop.key.name === "get" || prop.key.name === "set")) {

         isGetSet = sawGetSet = true;

         kind = prop.kind = prop.key.name;

         prop.key = parsePropertyName();

         if (tokType !== _parenL) unexpected();

         prop.value = parseFunction(startNode(), false);

       } else unexpected();

       // getters and setters are not allowed to clash — either with

       // each other or with an init property — and in strict mode,

       // init properties are also not allowed to be repeated.

       if (prop.key.type === "Identifier" && (strict || sawGetSet)) {

         for (var i = 0; i < node.properties.length; ++i) {

           var other = node.properties[i];

           if (other.key.name === prop.key.name) {

             var conflict = kind == other.kind || isGetSet && other.kind === "init" ||

               kind === "init" && (other.kind === "get" || other.kind === "set");

             if (conflict && !strict && kind === "init" && other.kind === "init") conflict = false;

             if (conflict) raise(prop.key.start, "Redefinition of property");

           }

         }

       }

       node.properties.push(prop);

     }

     return finishNode(node, "ObjectExpression");

   }

   function parsePropertyName() {

     if (tokType === _num || tokType === _string) return parseExprAtom();

     return parseIdent(true);

   }

   // Parse a function declaration or literal (depending on the

   // `isStatement` parameter).

   function parseFunction(node, isStatement) {

     if (tokType === _name) node.id = parseIdent();

     else if (isStatement) unexpected();

     else node.id = null;

     node.params = [];

     var first = true;

     expect(_parenL);

     while (!eat(_parenR)) {

       if (!first) expect(_comma); else first = false;

       node.params.push(parseIdent());

     }

     // Start a new scope with regard to labels and the `inFunction`

     // flag (restore them to their old value afterwards).

     var oldInFunc = inFunction, oldLabels = labels;

     inFunction = true; labels = [];

     node.body = parseBlock(true);

     inFunction = oldInFunc; labels = oldLabels;

     // If this is a strict mode function, verify that argument names

     // are not repeated, and it does not try to bind the words `eval`

     // or `arguments`.

     if (strict || node.body.body.length && isUseStrict(node.body.body[0])) {

       for (var i = node.id ? -1 : 0; i < node.params.length; ++i) {

         var id = i < 0 ? node.id : node.params[i];

         if (isStrictReservedWord(id.name) || isStrictBadIdWord(id.name))

           raise(id.start, "Defining '" + id.name + "' in strict mode");

         if (i >= 0) for (var j = 0; j < i; ++j) if (id.name === node.params[j].name)

           raise(id.start, "Argument name clash in strict mode");

       }

     }

     return finishNode(node, isStatement ? "FunctionDeclaration" : "FunctionExpression");

   }

   // Parses a comma-separated list of expressions, and returns them as

   // an array. `close` is the token type that ends the list, and

   // `allowEmpty` can be turned on to allow subsequent commas with

   // nothing in between them to be parsed as `null` (which is needed

   // for array literals).

   function parseExprList(close, allowTrailingComma, allowEmpty) {

     var elts = [], first = true;

     while (!eat(close)) {

       if (!first) {

         expect(_comma);

         if (allowTrailingComma && options.allowTrailingCommas && eat(close)) break;

       } else first = false;

       if (allowEmpty && tokType === _comma) elts.push(null);

       else elts.push(parseExpression(true));

     }

     return elts;

   }

   // Parse the next token as an identifier. If `liberal` is true (used

   // when parsing properties), it will also convert keywords into

   // identifiers.

   function parseIdent(liberal) {

     var node = startNode();

     node.name = tokType === _name ? tokVal : (liberal && !options.forbidReserved && tokType.keyword) || unexpected();

     tokRegexpAllowed = false;

     next();

     return finishNode(node, "Identifier");

   }

 });