diff --git a/package-lock.json b/package-lock.json
index 33b20a464..9f2982b5d 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -689,24 +689,9 @@
       }
     },
     "acorn": {
-      "version": "5.7.3",
-      "resolved": "https://registry.npmjs.org/acorn/-/acorn-5.7.3.tgz",
-      "integrity": "sha512-T/zvzYRfbVojPWahDsE5evJdHb3oJoQfFbsrKM7w5Zcs++Tr257tia3BmMP8XYVjp1S9RZXQMh7gao96BlqZOw=="
-    },
-    "acorn-dynamic-import": {
-      "version": "2.0.2",
-      "resolved": "https://registry.npmjs.org/acorn-dynamic-import/-/acorn-dynamic-import-2.0.2.tgz",
-      "integrity": "sha1-x1K9IQvvZ5UBtsbLf8hPj0cVjMQ=",
-      "requires": {
-        "acorn": "4.0.13"
-      },
-      "dependencies": {
-        "acorn": {
-          "version": "4.0.13",
-          "resolved": "https://registry.npmjs.org/acorn/-/acorn-4.0.13.tgz",
-          "integrity": "sha1-EFSVrlNh1pe9GVyCUZLhrX8lN4c="
-        }
-      }
+      "version": "6.2.0",
+      "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.2.0.tgz",
+      "integrity": "sha512-8oe72N3WPMjA+2zVG71Ia0nXZ8DpQH+QyyHO+p06jT8eg8FGG3FbcUIi8KziHlAfheJQZeoqbvq1mQSQHXKYLw=="
     },
     "acorn-globals": {
       "version": "4.3.2",
@@ -715,7 +700,7 @@
       "dev": true,
       "requires": {
         "acorn": "6.1.1",
-        "acorn-walk": "6.1.1"
+        "acorn-walk": "6.2.0"
       },
       "dependencies": {
         "acorn": {
@@ -744,9 +729,9 @@
       }
     },
     "acorn-walk": {
-      "version": "6.1.1",
-      "resolved": "https://registry.npmjs.org/acorn-walk/-/acorn-walk-6.1.1.tgz",
-      "integrity": "sha512-OtUw6JUTgxA2QoqqmrmQ7F2NYqiBPi/L2jqHyFtllhOUvXYQXf0Z1CYUinIfyT4bTCGmrA7gX9FvHA81uzCoVw=="
+      "version": "6.2.0",
+      "resolved": "https://registry.npmjs.org/acorn-walk/-/acorn-walk-6.2.0.tgz",
+      "integrity": "sha512-7evsyfH1cLOCdAzZAd43Cic04yKydNx0cF+7tiA19p1XnLLPU4dpCQOqpjqwokFe//vS0QqfqqjCS2JkiIs0cA=="
     },
     "ajv": {
       "version": "5.5.2",
diff --git a/package.json b/package.json
index aff6ee979..408f8ac1f 100644
--- a/package.json
+++ b/package.json
@@ -9,9 +9,8 @@
     "@types/numeral": "0.0.25",
     "@types/react": "^16.8.6",
     "@types/react-dom": "^16.8.2",
-    "acorn": "^5.7.3",
-    "acorn-dynamic-import": "^2.0.0",
-    "acorn-walk": "^6.1.1",
+    "acorn": "^6.2.0",
+    "acorn-walk": "^6.2.0",
     "ajv": "^5.1.5",
     "ajv-keywords": "^2.0.0",
     "async": "^2.6.1",
diff --git a/src/Fconf/Fconf.js b/src/Fconf/Fconf.js
index f40bcc8ce..7baa349a0 100644
--- a/src/Fconf/Fconf.js
+++ b/src/Fconf/Fconf.js
@@ -1,6 +1,6 @@
 import { FconfSettings }                        from "./FconfSettings";
 
-import { parse, Node }                          from "../../utils/acorn";
+import { parse, Node }                          from "acorn";
 import { dialogBoxCreate }                      from "../../utils/DialogBox";
 
 var FconfComments = {
diff --git a/src/JSInterpreter.js b/src/JSInterpreter.js
index d9dfb3327..145423c44 100644
--- a/src/JSInterpreter.js
+++ b/src/JSInterpreter.js
@@ -1,4 +1,4 @@
-import * as acorn from "../utils/acorn";
+import * as acorn from "acorn";
 /**
  * @license
  * JavaScript Interpreter
diff --git a/src/NetscriptEvaluator.js b/src/NetscriptEvaluator.js
index 323919ad4..cdd0c5636 100644
--- a/src/NetscriptEvaluator.js
+++ b/src/NetscriptEvaluator.js
@@ -1,5 +1,4 @@
 import { setTimeoutRef } from "./utils/SetTimeoutRef";
-import { parse, Node } from "../utils/acorn";
 
 import { isValidIPAddress } from "../utils/helpers/isValidIPAddress";
 import { isString } from "../utils/helpers/isString";
diff --git a/src/NetscriptWorker.js b/src/NetscriptWorker.js
index 65390a3eb..9e09c771d 100644
--- a/src/NetscriptWorker.js
+++ b/src/NetscriptWorker.js
@@ -30,14 +30,14 @@ import { setTimeoutRef } from "./utils/SetTimeoutRef";
 
 import { generate } from "escodegen";
 
-import { parse, Node } from "../utils/acorn";
 import { dialogBoxCreate } from "../utils/DialogBox";
 import { compareArrays } from "../utils/helpers/compareArrays";
 import { arrayToString } from "../utils/helpers/arrayToString";
 import { roundToTwo } from "../utils/helpers/roundToTwo";
 import { isString } from "../utils/StringHelperFunctions";
 
-const walk  = require("acorn/dist/walk");
+import { parse, Node } from "acorn";
+const walk = require("acorn-walk");
 
 // Netscript Ports are instantiated here
 export const NetscriptPorts = [];
@@ -288,7 +288,7 @@ function startNetscript1Script(workerScript) {
 */
 function processNetscript1Imports(code, workerScript) {
     //allowReserved prevents 'import' from throwing error in ES5
-    const ast = parse(code, { ecmaVersion: 6, allowReserved: true, sourceType: "module" });
+    const ast = parse(code, { ecmaVersion: 9, allowReserved: true, sourceType: "module" });
 
     var server = workerScript.getServer();
     if (server == null) {
@@ -319,7 +319,7 @@ function processNetscript1Imports(code, workerScript) {
             if (script == null) {
                 throw new Error("'Import' failed due to invalid script: " + scriptName);
             }
-            let scriptAst = parse(script.code, {ecmaVersion:5, allowReserved:true, sourceType:"module"});
+            let scriptAst = parse(script.code, { ecmaVersion:9, allowReserved:true, sourceType:"module" });
 
             if (node.specifiers.length === 1 && node.specifiers[0].type === "ImportNamespaceSpecifier") {
                 // import * as namespace from script
@@ -535,7 +535,7 @@ export function createAndAddWorkerScript(runningScriptObj, server) {
         // already stopped somewhere else (maybe by something like exit()). This prevents
         // the script from being cleaned up twice
         if (!w.running) { return; }
-        
+
         console.log("Stopping script " + w.name + " because it finished running naturally");
         killWorkerScript(s);
         w.log("Script finished running");
diff --git a/src/Script/RamCalculations.js b/src/Script/RamCalculations.js
index 1d2a77823..5d2792a3c 100644
--- a/src/Script/RamCalculations.js
+++ b/src/Script/RamCalculations.js
@@ -6,11 +6,11 @@
  * the way
  */
 import * as walk from "acorn-walk";
+import { parse, Node } from "acorn";
 
 import { RamCalculationErrorCode } from "./RamCalculationErrorCodes";
 
 import { RamCosts, RamCostConstants } from "../Netscript/RamCostGenerator";
-import { parse, Node } from "../../utils/acorn";
 
 // These special strings are used to reference the presence of a given logical
 // construct within a user script.
@@ -215,7 +215,7 @@ async function parseOnlyRamCalculate(otherScripts, code, workerScript) {
  * that need to be parsed (i.e. are 'import'ed scripts).
  */
 function parseOnlyCalculateDeps(code, currentModule) {
-    const ast = parse(code, {sourceType:"module", ecmaVersion: 8});
+    const ast = parse(code, {sourceType:"module", ecmaVersion: 9});
 
     // Everything from the global scope goes in ".". Everything else goes in ".function", where only
     // the outermost layer of functions counts.
diff --git a/src/ScriptEditor/CodeMirrorNetscriptLint.js b/src/ScriptEditor/CodeMirrorNetscriptLint.js
index 35542901a..c83f77ef8 100644
--- a/src/ScriptEditor/CodeMirrorNetscriptLint.js
+++ b/src/ScriptEditor/CodeMirrorNetscriptLint.js
@@ -37,7 +37,7 @@
     if (!options.indent) // JSHint error.character actually is a column index, this fixes underlining on lines using tabs for indentation
       options.indent = 1; // JSHint default value is 4
 
-    options.esversion = 6;
+    options.esversion = 9;
 
     JSHINT(sanitizedText, options, options.globals);
     var errors = JSHINT.data().errors, result = [];
diff --git a/utils/acorn.js b/utils/acorn.js
deleted file mode 100644
index 978089afd..000000000
--- a/utils/acorn.js
+++ /dev/null
@@ -1,3631 +0,0 @@
-/*
-acorn.js 
-https://github.com/ternjs/acorn
-
-Copyright (C) 2012-2017 by various contributors (see AUTHORS)
-
-Permission is hereby granted, free of charge, to any person obtaining a copy
-of this software and associated documentation files (the "Software"), to deal
-in the Software without restriction, including without limitation the rights
-to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-copies of the Software, and to permit persons to whom the Software is
-furnished to do so, subject to the following conditions:
-
-The above copyright notice and this permission notice shall be included in
-all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-THE SOFTWARE.
-*/
-
-(function (global, factory) {
-  typeof exports === 'object' && typeof module !== 'undefined' ? factory(exports) :
-  typeof define === 'function' && define.amd ? define(['exports'], factory) :
-  (factory((global.acorn = global.acorn || {})));
-}(this, (function (exports) { 'use strict';
-
-// Reserved word lists for various dialects of the language
-
-var reservedWords = {
-  3: "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",
-  5: "class enum extends super const export import",
-  6: "enum",
-  strict: "implements interface let package private protected public static yield",
-  strictBind: "eval arguments"
-}
-
-// And the keywords
-
-var ecma5AndLessKeywords = "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"
-
-var keywords = {
-  5: ecma5AndLessKeywords,
-  6: ecma5AndLessKeywords + " const class extends export import super"
-}
-
-// ## 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.
-// Generated by `bin/generate-identifier-regex.js`.
-
-var nonASCIIidentifierStartChars = "\xaa\xb5\xba\xc0-\xd6\xd8-\xf6\xf8-\u02c1\u02c6-\u02d1\u02e0-\u02e4\u02ec\u02ee\u0370-\u0374\u0376\u0377\u037a-\u037d\u037f\u0386\u0388-\u038a\u038c\u038e-\u03a1\u03a3-\u03f5\u03f7-\u0481\u048a-\u052f\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-\u08b4\u08b6-\u08bd\u0904-\u0939\u093d\u0950\u0958-\u0961\u0971-\u0980\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\u0af9\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-\u0c39\u0c3d\u0c58-\u0c5a\u0c60\u0c61\u0c80\u0c85-\u0c8c\u0c8e-\u0c90\u0c92-\u0ca8\u0caa-\u0cb3\u0cb5-\u0cb9\u0cbd\u0cde\u0ce0\u0ce1\u0cf1\u0cf2\u0d05-\u0d0c\u0d0e-\u0d10\u0d12-\u0d3a\u0d3d\u0d4e\u0d54-\u0d56\u0d5f-\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-\u13f5\u13f8-\u13fd\u1401-\u166c\u166f-\u167f\u1681-\u169a\u16a0-\u16ea\u16ee-\u16f8\u1700-\u170c\u170e-\u1711\u1720-\u1731\u1740-\u1751\u1760-\u176c\u176e-\u1770\u1780-\u17b3\u17d7\u17dc\u1820-\u1877\u1880-\u18a8\u18aa\u18b0-\u18f5\u1900-\u191e\u1950-\u196d\u1970-\u1974\u1980-\u19ab\u19b0-\u19c9\u1a00-\u1a16\u1a20-\u1a54\u1aa7\u1b05-\u1b33\u1b45-\u1b4b\u1b83-\u1ba0\u1bae\u1baf\u1bba-\u1be5\u1c00-\u1c23\u1c4d-\u1c4f\u1c5a-\u1c7d\u1c80-\u1c88\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\u2118-\u211d\u2124\u2126\u2128\u212a-\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\u3005-\u3007\u3021-\u3029\u3031-\u3035\u3038-\u303c\u3041-\u3096\u309b-\u309f\u30a1-\u30fa\u30fc-\u30ff\u3105-\u312d\u3131-\u318e\u31a0-\u31ba\u31f0-\u31ff\u3400-\u4db5\u4e00-\u9fd5\ua000-\ua48c\ua4d0-\ua4fd\ua500-\ua60c\ua610-\ua61f\ua62a\ua62b\ua640-\ua66e\ua67f-\ua69d\ua6a0-\ua6ef\ua717-\ua71f\ua722-\ua788\ua78b-\ua7ae\ua7b0-\ua7b7\ua7f7-\ua801\ua803-\ua805\ua807-\ua80a\ua80c-\ua822\ua840-\ua873\ua882-\ua8b3\ua8f2-\ua8f7\ua8fb\ua8fd\ua90a-\ua925\ua930-\ua946\ua960-\ua97c\ua984-\ua9b2\ua9cf\ua9e0-\ua9e4\ua9e6-\ua9ef\ua9fa-\ua9fe\uaa00-\uaa28\uaa40-\uaa42\uaa44-\uaa4b\uaa60-\uaa76\uaa7a\uaa7e-\uaaaf\uaab1\uaab5\uaab6\uaab9-\uaabd\uaac0\uaac2\uaadb-\uaadd\uaae0-\uaaea\uaaf2-\uaaf4\uab01-\uab06\uab09-\uab0e\uab11-\uab16\uab20-\uab26\uab28-\uab2e\uab30-\uab5a\uab5c-\uab65\uab70-\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 = "\u200c\u200d\xb7\u0300-\u036f\u0387\u0483-\u0487\u0591-\u05bd\u05bf\u05c1\u05c2\u05c4\u05c5\u05c7\u0610-\u061a\u064b-\u0669\u0670\u06d6-\u06dc\u06df-\u06e4\u06e7\u06e8\u06ea-\u06ed\u06f0-\u06f9\u0711\u0730-\u074a\u07a6-\u07b0\u07c0-\u07c9\u07eb-\u07f3\u0816-\u0819\u081b-\u0823\u0825-\u0827\u0829-\u082d\u0859-\u085b\u08d4-\u08e1\u08e3-\u0903\u093a-\u093c\u093e-\u094f\u0951-\u0957\u0962\u0963\u0966-\u096f\u0981-\u0983\u09bc\u09be-\u09c4\u09c7\u09c8\u09cb-\u09cd\u09d7\u09e2\u09e3\u09e6-\u09ef\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\u0b62\u0b63\u0b66-\u0b6f\u0b82\u0bbe-\u0bc2\u0bc6-\u0bc8\u0bca-\u0bcd\u0bd7\u0be6-\u0bef\u0c00-\u0c03\u0c3e-\u0c44\u0c46-\u0c48\u0c4a-\u0c4d\u0c55\u0c56\u0c62\u0c63\u0c66-\u0c6f\u0c81-\u0c83\u0cbc\u0cbe-\u0cc4\u0cc6-\u0cc8\u0cca-\u0ccd\u0cd5\u0cd6\u0ce2\u0ce3\u0ce6-\u0cef\u0d01-\u0d03\u0d3e-\u0d44\u0d46-\u0d48\u0d4a-\u0d4d\u0d57\u0d62\u0d63\u0d66-\u0d6f\u0d82\u0d83\u0dca\u0dcf-\u0dd4\u0dd6\u0dd8-\u0ddf\u0de6-\u0def\u0df2\u0df3\u0e31\u0e34-\u0e3a\u0e47-\u0e4e\u0e50-\u0e59\u0eb1\u0eb4-\u0eb9\u0ebb\u0ebc\u0ec8-\u0ecd\u0ed0-\u0ed9\u0f18\u0f19\u0f20-\u0f29\u0f35\u0f37\u0f39\u0f3e\u0f3f\u0f71-\u0f84\u0f86\u0f87\u0f8d-\u0f97\u0f99-\u0fbc\u0fc6\u102b-\u103e\u1040-\u1049\u1056-\u1059\u105e-\u1060\u1062-\u1064\u1067-\u106d\u1071-\u1074\u1082-\u108d\u108f-\u109d\u135d-\u135f\u1369-\u1371\u1712-\u1714\u1732-\u1734\u1752\u1753\u1772\u1773\u17b4-\u17d3\u17dd\u17e0-\u17e9\u180b-\u180d\u1810-\u1819\u18a9\u1920-\u192b\u1930-\u193b\u1946-\u194f\u19d0-\u19da\u1a17-\u1a1b\u1a55-\u1a5e\u1a60-\u1a7c\u1a7f-\u1a89\u1a90-\u1a99\u1ab0-\u1abd\u1b00-\u1b04\u1b34-\u1b44\u1b50-\u1b59\u1b6b-\u1b73\u1b80-\u1b82\u1ba1-\u1bad\u1bb0-\u1bb9\u1be6-\u1bf3\u1c24-\u1c37\u1c40-\u1c49\u1c50-\u1c59\u1cd0-\u1cd2\u1cd4-\u1ce8\u1ced\u1cf2-\u1cf4\u1cf8\u1cf9\u1dc0-\u1df5\u1dfb-\u1dff\u203f\u2040\u2054\u20d0-\u20dc\u20e1\u20e5-\u20f0\u2cef-\u2cf1\u2d7f\u2de0-\u2dff\u302a-\u302f\u3099\u309a\ua620-\ua629\ua66f\ua674-\ua67d\ua69e\ua69f\ua6f0\ua6f1\ua802\ua806\ua80b\ua823-\ua827\ua880\ua881\ua8b4-\ua8c5\ua8d0-\ua8d9\ua8e0-\ua8f1\ua900-\ua909\ua926-\ua92d\ua947-\ua953\ua980-\ua983\ua9b3-\ua9c0\ua9d0-\ua9d9\ua9e5\ua9f0-\ua9f9\uaa29-\uaa36\uaa43\uaa4c\uaa4d\uaa50-\uaa59\uaa7b-\uaa7d\uaab0\uaab2-\uaab4\uaab7\uaab8\uaabe\uaabf\uaac1\uaaeb-\uaaef\uaaf5\uaaf6\uabe3-\uabea\uabec\uabed\uabf0-\uabf9\ufb1e\ufe00-\ufe0f\ufe20-\ufe2f\ufe33\ufe34\ufe4d-\ufe4f\uff10-\uff19\uff3f"
-
-var nonASCIIidentifierStart = new RegExp("[" + nonASCIIidentifierStartChars + "]")
-var nonASCIIidentifier = new RegExp("[" + nonASCIIidentifierStartChars + nonASCIIidentifierChars + "]")
-
-nonASCIIidentifierStartChars = nonASCIIidentifierChars = null
-
-// These are a run-length and offset encoded representation of the
-// >0xffff code points that are a valid part of identifiers. The
-// offset starts at 0x10000, and each pair of numbers represents an
-// offset to the next range, and then a size of the range. They were
-// generated by bin/generate-identifier-regex.js
-
-// eslint-disable-next-line comma-spacing
-var astralIdentifierStartCodes = [0,11,2,25,2,18,2,1,2,14,3,13,35,122,70,52,268,28,4,48,48,31,17,26,6,37,11,29,3,35,5,7,2,4,43,157,19,35,5,35,5,39,9,51,157,310,10,21,11,7,153,5,3,0,2,43,2,1,4,0,3,22,11,22,10,30,66,18,2,1,11,21,11,25,71,55,7,1,65,0,16,3,2,2,2,26,45,28,4,28,36,7,2,27,28,53,11,21,11,18,14,17,111,72,56,50,14,50,785,52,76,44,33,24,27,35,42,34,4,0,13,47,15,3,22,0,2,0,36,17,2,24,85,6,2,0,2,3,2,14,2,9,8,46,39,7,3,1,3,21,2,6,2,1,2,4,4,0,19,0,13,4,159,52,19,3,54,47,21,1,2,0,185,46,42,3,37,47,21,0,60,42,86,25,391,63,32,0,449,56,264,8,2,36,18,0,50,29,881,921,103,110,18,195,2749,1070,4050,582,8634,568,8,30,114,29,19,47,17,3,32,20,6,18,881,68,12,0,67,12,65,0,32,6124,20,754,9486,1,3071,106,6,12,4,8,8,9,5991,84,2,70,2,1,3,0,3,1,3,3,2,11,2,0,2,6,2,64,2,3,3,7,2,6,2,27,2,3,2,4,2,0,4,6,2,339,3,24,2,24,2,30,2,24,2,30,2,24,2,30,2,24,2,30,2,24,2,7,4149,196,60,67,1213,3,2,26,2,1,2,0,3,0,2,9,2,3,2,0,2,0,7,0,5,0,2,0,2,0,2,2,2,1,2,0,3,0,2,0,2,0,2,0,2,0,2,1,2,0,3,3,2,6,2,3,2,3,2,0,2,9,2,16,6,2,2,4,2,16,4421,42710,42,4148,12,221,3,5761,10591,541]
-
-// eslint-disable-next-line comma-spacing
-var astralIdentifierCodes = [509,0,227,0,150,4,294,9,1368,2,2,1,6,3,41,2,5,0,166,1,1306,2,54,14,32,9,16,3,46,10,54,9,7,2,37,13,2,9,52,0,13,2,49,13,10,2,4,9,83,11,7,0,161,11,6,9,7,3,57,0,2,6,3,1,3,2,10,0,11,1,3,6,4,4,193,17,10,9,87,19,13,9,214,6,3,8,28,1,83,16,16,9,82,12,9,9,84,14,5,9,423,9,838,7,2,7,17,9,57,21,2,13,19882,9,135,4,60,6,26,9,1016,45,17,3,19723,1,5319,4,4,5,9,7,3,6,31,3,149,2,1418,49,513,54,5,49,9,0,15,0,23,4,2,14,1361,6,2,16,3,6,2,1,2,4,2214,6,110,6,6,9,792487,239]
-
-// This has a complexity linear to the value of the code. The
-// assumption is that looking up astral identifier characters is
-// rare.
-function isInAstralSet(code, set) {
-  var pos = 0x10000
-  for (var i = 0; i < set.length; i += 2) {
-    pos += set[i]
-    if (pos > code) return false
-    pos += set[i + 1]
-    if (pos >= code) return true
-  }
-}
-
-// Test whether a given character code starts an identifier.
-
-function isIdentifierStart(code, astral) {
-  if (code < 65) return code === 36
-  if (code < 91) return true
-  if (code < 97) return code === 95
-  if (code < 123) return true
-  if (code <= 0xffff) return code >= 0xaa && nonASCIIidentifierStart.test(String.fromCharCode(code))
-  if (astral === false) return false
-  return isInAstralSet(code, astralIdentifierStartCodes)
-}
-
-// Test whether a given character is part of an identifier.
-
-function isIdentifierChar(code, astral) {
-  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
-  if (code <= 0xffff) return code >= 0xaa && nonASCIIidentifier.test(String.fromCharCode(code))
-  if (astral === false) return false
-  return isInAstralSet(code, astralIdentifierStartCodes) || isInAstralSet(code, astralIdentifierCodes)
-}
-
-// ## 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.
-
-// 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).
-//
-// The `startsExpr` property is used to check if the token ends a
-// `yield` expression. It is set on all token types that either can
-// directly start an expression (like a quotation mark) or can
-// continue an expression (like the body of a string).
-//
-// `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 TokenType = function TokenType(label, conf) {
-  if ( conf === void 0 ) conf = {};
-
-  this.label = label
-  this.keyword = conf.keyword
-  this.beforeExpr = !!conf.beforeExpr
-  this.startsExpr = !!conf.startsExpr
-  this.isLoop = !!conf.isLoop
-  this.isAssign = !!conf.isAssign
-  this.prefix = !!conf.prefix
-  this.postfix = !!conf.postfix
-  this.binop = conf.binop || null
-  this.updateContext = null
-};
-
-function binop(name, prec) {
-  return new TokenType(name, {beforeExpr: true, binop: prec})
-}
-var beforeExpr = {beforeExpr: true};
-var startsExpr = {startsExpr: true};
-// Map keyword names to token types.
-
-var keywordTypes = {}
-
-// Succinct definitions of keyword token types
-function kw(name, options) {
-  if ( options === void 0 ) options = {};
-
-  options.keyword = name
-  return keywordTypes[name] = new TokenType(name, options)
-}
-
-var tt = {
-  num: new TokenType("num", startsExpr),
-  regexp: new TokenType("regexp", startsExpr),
-  string: new TokenType("string", startsExpr),
-  name: new TokenType("name", startsExpr),
-  eof: new TokenType("eof"),
-
-  // Punctuation token types.
-  bracketL: new TokenType("[", {beforeExpr: true, startsExpr: true}),
-  bracketR: new TokenType("]"),
-  braceL: new TokenType("{", {beforeExpr: true, startsExpr: true}),
-  braceR: new TokenType("}"),
-  parenL: new TokenType("(", {beforeExpr: true, startsExpr: true}),
-  parenR: new TokenType(")"),
-  comma: new TokenType(",", beforeExpr),
-  semi: new TokenType(";", beforeExpr),
-  colon: new TokenType(":", beforeExpr),
-  dot: new TokenType("."),
-  question: new TokenType("?", beforeExpr),
-  arrow: new TokenType("=>", beforeExpr),
-  template: new TokenType("template"),
-  ellipsis: new TokenType("...", beforeExpr),
-  backQuote: new TokenType("`", startsExpr),
-  dollarBraceL: new TokenType("${", {beforeExpr: true, startsExpr: 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.
-  //
-  // `isAssign` marks all of `=`, `+=`, `-=` etcetera, which act as
-  // binary operators with a very low precedence, that should result
-  // in AssignmentExpression nodes.
-
-  eq: new TokenType("=", {beforeExpr: true, isAssign: true}),
-  assign: new TokenType("_=", {beforeExpr: true, isAssign: true}),
-  incDec: new TokenType("++/--", {prefix: true, postfix: true, startsExpr: true}),
-  prefix: new TokenType("prefix", {beforeExpr: true, prefix: true, startsExpr: true}),
-  logicalOR: binop("||", 1),
-  logicalAND: binop("&&", 2),
-  bitwiseOR: binop("|", 3),
-  bitwiseXOR: binop("^", 4),
-  bitwiseAND: binop("&", 5),
-  equality: binop("==/!=", 6),
-  relational: binop("</>", 7),
-  bitShift: binop("<</>>", 8),
-  plusMin: new TokenType("+/-", {beforeExpr: true, binop: 9, prefix: true, startsExpr: true}),
-  modulo: binop("%", 10),
-  star: binop("*", 10),
-  slash: binop("/", 10),
-  starstar: new TokenType("**", {beforeExpr: true}),
-
-  // Keyword token types.
-  _break: kw("break"),
-  _case: kw("case", beforeExpr),
-  _catch: kw("catch"),
-  _continue: kw("continue"),
-  _debugger: kw("debugger"),
-  _default: kw("default", beforeExpr),
-  _do: kw("do", {isLoop: true, beforeExpr: true}),
-  _else: kw("else", beforeExpr),
-  _finally: kw("finally"),
-  _for: kw("for", {isLoop: true}),
-  _function: kw("function", startsExpr),
-  _if: kw("if"),
-  _return: kw("return", beforeExpr),
-  _switch: kw("switch"),
-  _throw: kw("throw", beforeExpr),
-  _try: kw("try"),
-  _var: kw("var"),
-  _const: kw("const"),
-  _while: kw("while", {isLoop: true}),
-  _with: kw("with"),
-  _new: kw("new", {beforeExpr: true, startsExpr: true}),
-  _this: kw("this", startsExpr),
-  _super: kw("super", startsExpr),
-  _class: kw("class"),
-  _extends: kw("extends", beforeExpr),
-  _export: kw("export"),
-  _import: kw("import"),
-  _null: kw("null", startsExpr),
-  _true: kw("true", startsExpr),
-  _false: kw("false", startsExpr),
-  _in: kw("in", {beforeExpr: true, binop: 7}),
-  _instanceof: kw("instanceof", {beforeExpr: true, binop: 7}),
-  _typeof: kw("typeof", {beforeExpr: true, prefix: true, startsExpr: true}),
-  _void: kw("void", {beforeExpr: true, prefix: true, startsExpr: true}),
-  _delete: kw("delete", {beforeExpr: true, prefix: true, startsExpr: true})
-}
-
-// Matches a whole line break (where CRLF is considered a single
-// line break). Used to count lines.
-
-var lineBreak = /\r\n?|\n|\u2028|\u2029/
-var lineBreakG = new RegExp(lineBreak.source, "g")
-
-function isNewLine(code) {
-  return code === 10 || code === 13 || code === 0x2028 || code === 0x2029
-}
-
-var nonASCIIwhitespace = /[\u1680\u180e\u2000-\u200a\u202f\u205f\u3000\ufeff]/
-
-var skipWhiteSpace = /(?:\s|\/\/.*|\/\*[^]*?\*\/)*/g
-
-var ref = Object.prototype;
-var hasOwnProperty = ref.hasOwnProperty;
-var toString = ref.toString;
-
-// Checks if an object has a property.
-
-function has(obj, propName) {
-  return hasOwnProperty.call(obj, propName)
-}
-
-var isArray = Array.isArray || (function (obj) { return (
-  toString.call(obj) === "[object Array]"
-); })
-
-// These are used when `options.locations` is on, for the
-// `startLoc` and `endLoc` properties.
-
-var Position = function Position(line, col) {
-  this.line = line
-  this.column = col
-};
-
-Position.prototype.offset = function offset (n) {
-  return new Position(this.line, this.column + n)
-};
-
-var SourceLocation = function SourceLocation(p, start, end) {
-  this.start = start
-  this.end = end
-  if (p.sourceFile !== null) this.source = p.sourceFile
-};
-
-// 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.
-
-function getLineInfo(input, offset) {
-  for (var line = 1, cur = 0;;) {
-    lineBreakG.lastIndex = cur
-    var match = lineBreakG.exec(input)
-    if (match && match.index < offset) {
-      ++line
-      cur = match.index + match[0].length
-    } else {
-      return new Position(line, offset - cur)
-    }
-  }
-}
-
-// A second optional argument can be given to further configure
-// the parser process. These options are recognized:
-
-var defaultOptions = {
-  // `ecmaVersion` indicates the ECMAScript version to parse. Must
-  // be either 3, 5, 6 (2015), 7 (2016), or 8 (2017). This influences support
-  // for strict mode, the set of reserved words, and support for
-  // new syntax features. The default is 7.
-  ecmaVersion: 7,
-  // `sourceType` indicates the mode the code should be parsed in.
-  // Can be either `"script"` or `"module"`. This influences global
-  // strict mode and parsing of `import` and `export` declarations.
-  sourceType: "script",
-  // `onInsertedSemicolon` can be a callback that will be called
-  // when a semicolon is automatically inserted. It will be passed
-  // th position of the comma as an offset, and if `locations` is
-  // enabled, it is given the location as a `{line, column}` object
-  // as second argument.
-  onInsertedSemicolon: null,
-  // `onTrailingComma` is similar to `onInsertedSemicolon`, but for
-  // trailing commas.
-  onTrailingComma: null,
-  // By default, reserved words are only enforced if ecmaVersion >= 5.
-  // Set `allowReserved` to a boolean value to explicitly turn this on
-  // an off. When this option has the value "never", reserved words
-  // and keywords can also not be used as property names.
-  allowReserved: null,
-  // When enabled, a return at the top level is not considered an
-  // error.
-  allowReturnOutsideFunction: false,
-  // When enabled, import/export statements are not constrained to
-  // appearing at the top of the program.
-  allowImportExportEverywhere: false,
-  // When enabled, hashbang directive in the beginning of file
-  // is allowed and treated as a line comment.
-  allowHashBang: 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 `onToken` option, which will
-  // cause Acorn to call that function with object in the same
-  // format as tokens returned from `tokenizer().getToken()`. Note
-  // that you are not allowed to call the parser from the
-  // callback—that will corrupt its internal state.
-  onToken: null,
-  // 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,
-  // When enabled, parenthesized expressions are represented by
-  // (non-standard) ParenthesizedExpression nodes
-  preserveParens: false,
-  plugins: {}
-}
-
-// Interpret and default an options object
-
-function getOptions(opts) {
-  var options = {}
-
-  for (var opt in defaultOptions)
-    options[opt] = opts && has(opts, opt) ? opts[opt] : defaultOptions[opt]
-
-  if (options.ecmaVersion >= 2015)
-    options.ecmaVersion -= 2009
-
-  if (options.allowReserved == null)
-    options.allowReserved = options.ecmaVersion < 5
-
-  if (isArray(options.onToken)) {
-    var tokens = options.onToken
-    options.onToken = function (token) { return tokens.push(token); }
-  }
-  if (isArray(options.onComment))
-    options.onComment = pushComment(options, options.onComment)
-
-  return options
-}
-
-function pushComment(options, array) {
-  return function(block, text, start, end, startLoc, endLoc) {
-    var comment = {
-      type: block ? "Block" : "Line",
-      value: text,
-      start: start,
-      end: end
-    }
-    if (options.locations)
-      comment.loc = new SourceLocation(this, startLoc, endLoc)
-    if (options.ranges)
-      comment.range = [start, end]
-    array.push(comment)
-  }
-}
-
-// Registered plugins
-var plugins = {}
-
-function keywordRegexp(words) {
-  return new RegExp("^(" + words.replace(/ /g, "|") + ")$")
-}
-
-var Parser = function Parser(options, input, startPos) {
-  this.options = options = getOptions(options)
-  this.sourceFile = options.sourceFile
-  this.keywords = keywordRegexp(keywords[options.ecmaVersion >= 6 ? 6 : 5])
-  var reserved = ""
-  if (!options.allowReserved) {
-    for (var v = options.ecmaVersion;; v--)
-      if (reserved = reservedWords[v]) break
-    if (options.sourceType == "module") reserved += " await"
-  }
-  this.reservedWords = keywordRegexp(reserved)
-  var reservedStrict = (reserved ? reserved + " " : "") + reservedWords.strict
-  this.reservedWordsStrict = keywordRegexp(reservedStrict)
-  this.reservedWordsStrictBind = keywordRegexp(reservedStrict + " " + reservedWords.strictBind)
-  this.input = String(input)
-
-  // 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.
-  this.containsEsc = false
-
-  // Load plugins
-  this.loadPlugins(options.plugins)
-
-  // Set up token state
-
-  // The current position of the tokenizer in the input.
-  if (startPos) {
-    this.pos = startPos
-    this.lineStart = this.input.lastIndexOf("\n", startPos - 1) + 1
-    this.curLine = this.input.slice(0, this.lineStart).split(lineBreak).length
-  } else {
-    this.pos = this.lineStart = 0
-    this.curLine = 1
-  }
-
-  // Properties of the current token:
-  // Its type
-  this.type = tt.eof
-  // For tokens that include more information than their type, the value
-  this.value = null
-  // Its start and end offset
-  this.start = this.end = this.pos
-  // And, if locations are used, the {line, column} object
-  // corresponding to those offsets
-  this.startLoc = this.endLoc = this.curPosition()
-
-  // Position information for the previous token
-  this.lastTokEndLoc = this.lastTokStartLoc = null
-  this.lastTokStart = this.lastTokEnd = this.pos
-
-  // The context stack is used to superficially track syntactic
-  // context to predict whether a regular expression is allowed in a
-  // given position.
-  this.context = this.initialContext()
-  this.exprAllowed = true
-
-  // Figure out if it's a module code.
-  this.inModule = options.sourceType === "module"
-  this.strict = this.inModule || this.strictDirective(this.pos)
-
-  // Used to signify the start of a potential arrow function
-  this.potentialArrowAt = -1
-
-  // Flags to track whether we are in a function, a generator, an async function.
-  this.inFunction = this.inGenerator = this.inAsync = false
-  // Positions to delayed-check that yield/await does not exist in default parameters.
-  this.yieldPos = this.awaitPos = 0
-  // Labels in scope.
-  this.labels = []
-
-  // If enabled, skip leading hashbang line.
-  if (this.pos === 0 && options.allowHashBang && this.input.slice(0, 2) === "#!")
-    this.skipLineComment(2)
-
-  // Scope tracking for duplicate variable names (see scope.js)
-  this.scopeStack = []
-  this.enterFunctionScope()
-};
-
-// DEPRECATED Kept for backwards compatibility until 3.0 in case a plugin uses them
-Parser.prototype.isKeyword = function isKeyword (word) { return this.keywords.test(word) };
-Parser.prototype.isReservedWord = function isReservedWord (word) { return this.reservedWords.test(word) };
-
-Parser.prototype.extend = function extend (name, f) {
-  this[name] = f(this[name])
-};
-
-Parser.prototype.loadPlugins = function loadPlugins (pluginConfigs) {
-    var this$1 = this;
-
-  for (var name in pluginConfigs) {
-    var plugin = plugins[name]
-    if (!plugin) throw new Error("Plugin '" + name + "' not found")
-    plugin(this$1, pluginConfigs[name])
-  }
-};
-
-Parser.prototype.parse = function parse () {
-  var node = this.options.program || this.startNode()
-  this.nextToken()
-  return this.parseTopLevel(node)
-};
-
-var pp = Parser.prototype
-
-// ## Parser utilities
-
-var literal = /^(?:'((?:[^']|\.)*)'|"((?:[^"]|\.)*)"|;)/
-pp.strictDirective = function(start) {
-  var this$1 = this;
-
-  for (;;) {
-    skipWhiteSpace.lastIndex = start
-    start += skipWhiteSpace.exec(this$1.input)[0].length
-    var match = literal.exec(this$1.input.slice(start))
-    if (!match) return false
-    if ((match[1] || match[2]) == "use strict") return true
-    start += match[0].length
-  }
-}
-
-// Predicate that tests whether the next token is of the given
-// type, and if yes, consumes it as a side effect.
-
-pp.eat = function(type) {
-  if (this.type === type) {
-    this.next()
-    return true
-  } else {
-    return false
-  }
-}
-
-// Tests whether parsed token is a contextual keyword.
-
-pp.isContextual = function(name) {
-  return this.type === tt.name && this.value === name
-}
-
-// Consumes contextual keyword if possible.
-
-pp.eatContextual = function(name) {
-  return this.value === name && this.eat(tt.name)
-}
-
-// Asserts that following token is given contextual keyword.
-
-pp.expectContextual = function(name) {
-  if (!this.eatContextual(name)) this.unexpected()
-}
-
-// Test whether a semicolon can be inserted at the current position.
-
-pp.canInsertSemicolon = function() {
-  return this.type === tt.eof ||
-    this.type === tt.braceR ||
-    lineBreak.test(this.input.slice(this.lastTokEnd, this.start))
-}
-
-pp.insertSemicolon = function() {
-  if (this.canInsertSemicolon()) {
-    if (this.options.onInsertedSemicolon)
-      this.options.onInsertedSemicolon(this.lastTokEnd, this.lastTokEndLoc)
-    return true
-  }
-}
-
-// Consume a semicolon, or, failing that, see if we are allowed to
-// pretend that there is a semicolon at this position.
-
-pp.semicolon = function() {
-  if (!this.eat(tt.semi) && !this.insertSemicolon()) this.unexpected()
-}
-
-pp.afterTrailingComma = function(tokType, notNext) {
-  if (this.type == tokType) {
-    if (this.options.onTrailingComma)
-      this.options.onTrailingComma(this.lastTokStart, this.lastTokStartLoc)
-    if (!notNext)
-      this.next()
-    return true
-  }
-}
-
-// Expect a token of a given type. If found, consume it, otherwise,
-// raise an unexpected token error.
-
-pp.expect = function(type) {
-  this.eat(type) || this.unexpected()
-}
-
-// Raise an unexpected token error.
-
-pp.unexpected = function(pos) {
-  this.raise(pos != null ? pos : this.start, "Unexpected token")
-}
-
-var DestructuringErrors = function DestructuringErrors() {
-  this.shorthandAssign = this.trailingComma = this.parenthesizedAssign = this.parenthesizedBind = -1
-};
-
-pp.checkPatternErrors = function(refDestructuringErrors, isAssign) {
-  if (!refDestructuringErrors) return
-  if (refDestructuringErrors.trailingComma > -1)
-    this.raiseRecoverable(refDestructuringErrors.trailingComma, "Comma is not permitted after the rest element")
-  var parens = isAssign ? refDestructuringErrors.parenthesizedAssign : refDestructuringErrors.parenthesizedBind
-  if (parens > -1) this.raiseRecoverable(parens, "Parenthesized pattern")
-}
-
-pp.checkExpressionErrors = function(refDestructuringErrors, andThrow) {
-  var pos = refDestructuringErrors ? refDestructuringErrors.shorthandAssign : -1
-  if (!andThrow) return pos >= 0
-  if (pos > -1) this.raise(pos, "Shorthand property assignments are valid only in destructuring patterns")
-}
-
-pp.checkYieldAwaitInDefaultParams = function() {
-  if (this.yieldPos && (!this.awaitPos || this.yieldPos < this.awaitPos))
-    this.raise(this.yieldPos, "Yield expression cannot be a default value")
-  if (this.awaitPos)
-    this.raise(this.awaitPos, "Await expression cannot be a default value")
-}
-
-pp.isSimpleAssignTarget = function(expr) {
-  if (expr.type === "ParenthesizedExpression")
-    return this.isSimpleAssignTarget(expr.expression)
-  return expr.type === "Identifier" || expr.type === "MemberExpression"
-}
-
-var pp$1 = Parser.prototype
-
-// ### 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.
-
-pp$1.parseTopLevel = function(node) {
-  var this$1 = this;
-
-  var exports = {}
-  if (!node.body) node.body = []
-  while (this.type !== tt.eof) {
-    var stmt = this$1.parseStatement(true, true, exports)
-    node.body.push(stmt)
-  }
-  this.next()
-  if (this.options.ecmaVersion >= 6) {
-    node.sourceType = this.options.sourceType
-  }
-  return this.finishNode(node, "Program")
-}
-
-var loopLabel = {kind: "loop"};
-var switchLabel = {kind: "switch"};
-pp$1.isLet = function() {
-  if (this.type !== tt.name || this.options.ecmaVersion < 6 || this.value != "let") return false
-  skipWhiteSpace.lastIndex = this.pos
-  var skip = skipWhiteSpace.exec(this.input)
-  var next = this.pos + skip[0].length, nextCh = this.input.charCodeAt(next)
-  if (nextCh === 91 || nextCh == 123) return true // '{' and '['
-  if (isIdentifierStart(nextCh, true)) {
-    var pos = next + 1
-    while (isIdentifierChar(this.input.charCodeAt(pos), true)) ++pos
-    var ident = this.input.slice(next, pos)
-    if (!this.isKeyword(ident)) return true
-  }
-  return false
-}
-
-// check 'async [no LineTerminator here] function'
-// - 'async /*foo*/ function' is OK.
-// - 'async /*\n*/ function' is invalid.
-pp$1.isAsyncFunction = function() {
-  if (this.type !== tt.name || this.options.ecmaVersion < 8 || this.value != "async")
-    return false
-
-  skipWhiteSpace.lastIndex = this.pos
-  var skip = skipWhiteSpace.exec(this.input)
-  var next = this.pos + skip[0].length
-  return !lineBreak.test(this.input.slice(this.pos, next)) &&
-    this.input.slice(next, next + 8) === "function" &&
-    (next + 8 == this.input.length || !isIdentifierChar(this.input.charAt(next + 8)))
-}
-
-// 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.
-
-pp$1.parseStatement = function(declaration, topLevel, exports) {
-  var starttype = this.type, node = this.startNode(), kind
-
-  if (this.isLet()) {
-    starttype = tt._var
-    kind = "let"
-  }
-
-  // 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 tt._break: case tt._continue: return this.parseBreakContinueStatement(node, starttype.keyword)
-  case tt._debugger: return this.parseDebuggerStatement(node)
-  case tt._do: return this.parseDoStatement(node)
-  case tt._for: return this.parseForStatement(node)
-  case tt._function:
-    if (!declaration && this.options.ecmaVersion >= 6) this.unexpected()
-    return this.parseFunctionStatement(node, false)
-  case tt._class:
-    if (!declaration) this.unexpected()
-    return this.parseClass(node, true)
-  case tt._if: return this.parseIfStatement(node)
-  case tt._return: return this.parseReturnStatement(node)
-  case tt._switch: return this.parseSwitchStatement(node)
-  case tt._throw: return this.parseThrowStatement(node)
-  case tt._try: return this.parseTryStatement(node)
-  case tt._const: case tt._var:
-    kind = kind || this.value
-    if (!declaration && kind != "var") this.unexpected()
-    return this.parseVarStatement(node, kind)
-  case tt._while: return this.parseWhileStatement(node)
-  case tt._with: return this.parseWithStatement(node)
-  case tt.braceL: return this.parseBlock()
-  case tt.semi: return this.parseEmptyStatement(node)
-  case tt._export:
-  case tt._import:
-    if (!this.options.allowImportExportEverywhere) {
-      if (!topLevel)
-        this.raise(this.start, "'import' and 'export' may only appear at the top level")
-      if (!this.inModule)
-        this.raise(this.start, "'import' and 'export' may appear only with 'sourceType: module'")
-    }
-    return starttype === tt._import ? this.parseImport(node) : this.parseExport(node, exports)
-
-    // 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:
-    if (this.isAsyncFunction() && declaration) {
-      this.next()
-      return this.parseFunctionStatement(node, true)
-    }
-
-    var maybeName = this.value, expr = this.parseExpression()
-    if (starttype === tt.name && expr.type === "Identifier" && this.eat(tt.colon))
-      return this.parseLabeledStatement(node, maybeName, expr)
-    else return this.parseExpressionStatement(node, expr)
-  }
-}
-
-pp$1.parseBreakContinueStatement = function(node, keyword) {
-  var this$1 = this;
-
-  var isBreak = keyword == "break"
-  this.next()
-  if (this.eat(tt.semi) || this.insertSemicolon()) node.label = null
-  else if (this.type !== tt.name) this.unexpected()
-  else {
-    node.label = this.parseIdent()
-    this.semicolon()
-  }
-
-  // Verify that there is an actual destination to break or
-  // continue to.
-  var i = 0
-  for (; i < this.labels.length; ++i) {
-    var lab = this$1.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 === this.labels.length) this.raise(node.start, "Unsyntactic " + keyword)
-  return this.finishNode(node, isBreak ? "BreakStatement" : "ContinueStatement")
-}
-
-pp$1.parseDebuggerStatement = function(node) {
-  this.next()
-  this.semicolon()
-  return this.finishNode(node, "DebuggerStatement")
-}
-
-pp$1.parseDoStatement = function(node) {
-  this.next()
-  this.labels.push(loopLabel)
-  node.body = this.parseStatement(false)
-  this.labels.pop()
-  this.expect(tt._while)
-  node.test = this.parseParenExpression()
-  if (this.options.ecmaVersion >= 6)
-    this.eat(tt.semi)
-  else
-    this.semicolon()
-  return this.finishNode(node, "DoWhileStatement")
-}
-
-// Disambiguating between a `for` and a `for`/`in` or `for`/`of`
-// 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` or `of`. When there is no init
-// part (semicolon immediately after the opening parenthesis), it
-// is a regular `for` loop.
-
-pp$1.parseForStatement = function(node) {
-  this.next()
-  this.labels.push(loopLabel)
-  this.enterLexicalScope()
-  this.expect(tt.parenL)
-  if (this.type === tt.semi) return this.parseFor(node, null)
-  var isLet = this.isLet()
-  if (this.type === tt._var || this.type === tt._const || isLet) {
-    var init$1 = this.startNode(), kind = isLet ? "let" : this.value
-    this.next()
-    this.parseVar(init$1, true, kind)
-    this.finishNode(init$1, "VariableDeclaration")
-    if ((this.type === tt._in || (this.options.ecmaVersion >= 6 && this.isContextual("of"))) && init$1.declarations.length === 1 &&
-        !(kind !== "var" && init$1.declarations[0].init))
-      return this.parseForIn(node, init$1)
-    return this.parseFor(node, init$1)
-  }
-  var refDestructuringErrors = new DestructuringErrors
-  var init = this.parseExpression(true, refDestructuringErrors)
-  if (this.type === tt._in || (this.options.ecmaVersion >= 6 && this.isContextual("of"))) {
-    this.toAssignable(init)
-    this.checkLVal(init)
-    this.checkPatternErrors(refDestructuringErrors, true)
-    return this.parseForIn(node, init)
-  } else {
-    this.checkExpressionErrors(refDestructuringErrors, true)
-  }
-  return this.parseFor(node, init)
-}
-
-pp$1.parseFunctionStatement = function(node, isAsync) {
-  this.next()
-  return this.parseFunction(node, true, false, isAsync)
-}
-
-pp$1.isFunction = function() {
-  return this.type === tt._function || this.isAsyncFunction()
-}
-
-pp$1.parseIfStatement = function(node) {
-  this.next()
-  node.test = this.parseParenExpression()
-  // allow function declarations in branches, but only in non-strict mode
-  node.consequent = this.parseStatement(!this.strict && this.isFunction())
-  node.alternate = this.eat(tt._else) ? this.parseStatement(!this.strict && this.isFunction()) : null
-  return this.finishNode(node, "IfStatement")
-}
-
-pp$1.parseReturnStatement = function(node) {
-  if (!this.inFunction && !this.options.allowReturnOutsideFunction)
-    this.raise(this.start, "'return' outside of function")
-  this.next()
-
-  // In `return` (and `break`/`continue`), the keywords with
-  // optional arguments, we eagerly look for a semicolon or the
-  // possibility to insert one.
-
-  if (this.eat(tt.semi) || this.insertSemicolon()) node.argument = null
-  else { node.argument = this.parseExpression(); this.semicolon() }
-  return this.finishNode(node, "ReturnStatement")
-}
-
-pp$1.parseSwitchStatement = function(node) {
-  var this$1 = this;
-
-  this.next()
-  node.discriminant = this.parseParenExpression()
-  node.cases = []
-  this.expect(tt.braceL)
-  this.labels.push(switchLabel)
-  this.enterLexicalScope()
-
-  // Statements under must be grouped (by label) in SwitchCase
-  // nodes. `cur` is used to keep the node that we are currently
-  // adding statements to.
-
-  var cur
-  for (var sawDefault = false; this.type != tt.braceR;) {
-    if (this$1.type === tt._case || this$1.type === tt._default) {
-      var isCase = this$1.type === tt._case
-      if (cur) this$1.finishNode(cur, "SwitchCase")
-      node.cases.push(cur = this$1.startNode())
-      cur.consequent = []
-      this$1.next()
-      if (isCase) {
-        cur.test = this$1.parseExpression()
-      } else {
-        if (sawDefault) this$1.raiseRecoverable(this$1.lastTokStart, "Multiple default clauses")
-        sawDefault = true
-        cur.test = null
-      }
-      this$1.expect(tt.colon)
-    } else {
-      if (!cur) this$1.unexpected()
-      cur.consequent.push(this$1.parseStatement(true))
-    }
-  }
-  this.exitLexicalScope()
-  if (cur) this.finishNode(cur, "SwitchCase")
-  this.next() // Closing brace
-  this.labels.pop()
-  return this.finishNode(node, "SwitchStatement")
-}
-
-pp$1.parseThrowStatement = function(node) {
-  this.next()
-  if (lineBreak.test(this.input.slice(this.lastTokEnd, this.start)))
-    this.raise(this.lastTokEnd, "Illegal newline after throw")
-  node.argument = this.parseExpression()
-  this.semicolon()
-  return this.finishNode(node, "ThrowStatement")
-}
-
-// Reused empty array added for node fields that are always empty.
-
-var empty = []
-
-pp$1.parseTryStatement = function(node) {
-  this.next()
-  node.block = this.parseBlock()
-  node.handler = null
-  if (this.type === tt._catch) {
-    var clause = this.startNode()
-    this.next()
-    this.expect(tt.parenL)
-    clause.param = this.parseBindingAtom()
-    this.enterLexicalScope()
-    this.checkLVal(clause.param, "let")
-    this.expect(tt.parenR)
-    clause.body = this.parseBlock(false)
-    this.exitLexicalScope()
-    node.handler = this.finishNode(clause, "CatchClause")
-  }
-  node.finalizer = this.eat(tt._finally) ? this.parseBlock() : null
-  if (!node.handler && !node.finalizer)
-    this.raise(node.start, "Missing catch or finally clause")
-  return this.finishNode(node, "TryStatement")
-}
-
-pp$1.parseVarStatement = function(node, kind) {
-  this.next()
-  this.parseVar(node, false, kind)
-  this.semicolon()
-  return this.finishNode(node, "VariableDeclaration")
-}
-
-pp$1.parseWhileStatement = function(node) {
-  this.next()
-  node.test = this.parseParenExpression()
-  this.labels.push(loopLabel)
-  node.body = this.parseStatement(false)
-  this.labels.pop()
-  return this.finishNode(node, "WhileStatement")
-}
-
-pp$1.parseWithStatement = function(node) {
-  if (this.strict) this.raise(this.start, "'with' in strict mode")
-  this.next()
-  node.object = this.parseParenExpression()
-  node.body = this.parseStatement(false)
-  return this.finishNode(node, "WithStatement")
-}
-
-pp$1.parseEmptyStatement = function(node) {
-  this.next()
-  return this.finishNode(node, "EmptyStatement")
-}
-
-pp$1.parseLabeledStatement = function(node, maybeName, expr) {
-  var this$1 = this;
-
-  for (var i = 0; i < this.labels.length; ++i)
-    if (this$1.labels[i].name === maybeName) this$1.raise(expr.start, "Label '" + maybeName + "' is already declared")
-  var kind = this.type.isLoop ? "loop" : this.type === tt._switch ? "switch" : null
-  for (var i$1 = this.labels.length - 1; i$1 >= 0; i$1--) {
-    var label = this$1.labels[i$1]
-    if (label.statementStart == node.start) {
-      label.statementStart = this$1.start
-      label.kind = kind
-    } else break
-  }
-  this.labels.push({name: maybeName, kind: kind, statementStart: this.start})
-  node.body = this.parseStatement(true)
-  if (node.body.type == "ClassDeclaration" ||
-      node.body.type == "VariableDeclaration" && node.body.kind != "var" ||
-      node.body.type == "FunctionDeclaration" && (this.strict || node.body.generator))
-    this.raiseRecoverable(node.body.start, "Invalid labeled declaration")
-  this.labels.pop()
-  node.label = expr
-  return this.finishNode(node, "LabeledStatement")
-}
-
-pp$1.parseExpressionStatement = function(node, expr) {
-  node.expression = expr
-  this.semicolon()
-  return this.finishNode(node, "ExpressionStatement")
-}
-
-// Parse a semicolon-enclosed block of statements, handling `"use
-// strict"` declarations when `allowStrict` is true (used for
-// function bodies).
-
-pp$1.parseBlock = function(createNewLexicalScope) {
-  var this$1 = this;
-  if ( createNewLexicalScope === void 0 ) createNewLexicalScope = true;
-
-  var node = this.startNode()
-  node.body = []
-  this.expect(tt.braceL)
-  if (createNewLexicalScope) {
-    this.enterLexicalScope()
-  }
-  while (!this.eat(tt.braceR)) {
-    var stmt = this$1.parseStatement(true)
-    node.body.push(stmt)
-  }
-  if (createNewLexicalScope) {
-    this.exitLexicalScope()
-  }
-  return this.finishNode(node, "BlockStatement")
-}
-
-// Parse a regular `for` loop. The disambiguation code in
-// `parseStatement` will already have parsed the init statement or
-// expression.
-
-pp$1.parseFor = function(node, init) {
-  node.init = init
-  this.expect(tt.semi)
-  node.test = this.type === tt.semi ? null : this.parseExpression()
-  this.expect(tt.semi)
-  node.update = this.type === tt.parenR ? null : this.parseExpression()
-  this.expect(tt.parenR)
-  this.exitLexicalScope()
-  node.body = this.parseStatement(false)
-  this.labels.pop()
-  return this.finishNode(node, "ForStatement")
-}
-
-// Parse a `for`/`in` and `for`/`of` loop, which are almost
-// same from parser's perspective.
-
-pp$1.parseForIn = function(node, init) {
-  var type = this.type === tt._in ? "ForInStatement" : "ForOfStatement"
-  this.next()
-  node.left = init
-  node.right = this.parseExpression()
-  this.expect(tt.parenR)
-  this.exitLexicalScope()
-  node.body = this.parseStatement(false)
-  this.labels.pop()
-  return this.finishNode(node, type)
-}
-
-// Parse a list of variable declarations.
-
-pp$1.parseVar = function(node, isFor, kind) {
-  var this$1 = this;
-
-  node.declarations = []
-  node.kind = kind
-  for (;;) {
-    var decl = this$1.startNode()
-    this$1.parseVarId(decl, kind)
-    if (this$1.eat(tt.eq)) {
-      decl.init = this$1.parseMaybeAssign(isFor)
-    } else if (kind === "const" && !(this$1.type === tt._in || (this$1.options.ecmaVersion >= 6 && this$1.isContextual("of")))) {
-      this$1.unexpected()
-    } else if (decl.id.type != "Identifier" && !(isFor && (this$1.type === tt._in || this$1.isContextual("of")))) {
-      this$1.raise(this$1.lastTokEnd, "Complex binding patterns require an initialization value")
-    } else {
-      decl.init = null
-    }
-    node.declarations.push(this$1.finishNode(decl, "VariableDeclarator"))
-    if (!this$1.eat(tt.comma)) break
-  }
-  return node
-}
-
-pp$1.parseVarId = function(decl, kind) {
-  decl.id = this.parseBindingAtom(kind)
-  this.checkLVal(decl.id, kind, false)
-}
-
-// Parse a function declaration or literal (depending on the
-// `isStatement` parameter).
-
-pp$1.parseFunction = function(node, isStatement, allowExpressionBody, isAsync) {
-  this.initFunction(node)
-  if (this.options.ecmaVersion >= 6 && !isAsync)
-    node.generator = this.eat(tt.star)
-  if (this.options.ecmaVersion >= 8)
-    node.async = !!isAsync
-
-  if (isStatement) {
-    node.id = isStatement === "nullableID" && this.type != tt.name ? null : this.parseIdent()
-    if (node.id) {
-      this.checkLVal(node.id, "var")
-    }
-  }
-
-  var oldInGen = this.inGenerator, oldInAsync = this.inAsync,
-      oldYieldPos = this.yieldPos, oldAwaitPos = this.awaitPos, oldInFunc = this.inFunction
-  this.inGenerator = node.generator
-  this.inAsync = node.async
-  this.yieldPos = 0
-  this.awaitPos = 0
-  this.inFunction = true
-  this.enterFunctionScope()
-
-  if (!isStatement)
-    node.id = this.type == tt.name ? this.parseIdent() : null
-
-  this.parseFunctionParams(node)
-  this.parseFunctionBody(node, allowExpressionBody)
-
-  this.inGenerator = oldInGen
-  this.inAsync = oldInAsync
-  this.yieldPos = oldYieldPos
-  this.awaitPos = oldAwaitPos
-  this.inFunction = oldInFunc
-  return this.finishNode(node, isStatement ? "FunctionDeclaration" : "FunctionExpression")
-}
-
-pp$1.parseFunctionParams = function(node) {
-  this.expect(tt.parenL)
-  node.params = this.parseBindingList(tt.parenR, false, this.options.ecmaVersion >= 8, true)
-  this.checkYieldAwaitInDefaultParams()
-}
-
-// Parse a class declaration or literal (depending on the
-// `isStatement` parameter).
-
-pp$1.parseClass = function(node, isStatement) {
-  var this$1 = this;
-
-  this.next()
-
-  this.parseClassId(node, isStatement)
-  this.parseClassSuper(node)
-  var classBody = this.startNode()
-  var hadConstructor = false
-  classBody.body = []
-  this.expect(tt.braceL)
-  while (!this.eat(tt.braceR)) {
-    if (this$1.eat(tt.semi)) continue
-    var method = this$1.startNode()
-    var isGenerator = this$1.eat(tt.star)
-    var isAsync = false
-    var isMaybeStatic = this$1.type === tt.name && this$1.value === "static"
-    this$1.parsePropertyName(method)
-    method.static = isMaybeStatic && this$1.type !== tt.parenL
-    if (method.static) {
-      if (isGenerator) this$1.unexpected()
-      isGenerator = this$1.eat(tt.star)
-      this$1.parsePropertyName(method)
-    }
-    if (this$1.options.ecmaVersion >= 8 && !isGenerator && !method.computed &&
-        method.key.type === "Identifier" && method.key.name === "async" && this$1.type !== tt.parenL &&
-        !this$1.canInsertSemicolon()) {
-      isAsync = true
-      this$1.parsePropertyName(method)
-    }
-    method.kind = "method"
-    var isGetSet = false
-    if (!method.computed) {
-      var key = method.key;
-      if (!isGenerator && !isAsync && key.type === "Identifier" && this$1.type !== tt.parenL && (key.name === "get" || key.name === "set")) {
-        isGetSet = true
-        method.kind = key.name
-        key = this$1.parsePropertyName(method)
-      }
-      if (!method.static && (key.type === "Identifier" && key.name === "constructor" ||
-          key.type === "Literal" && key.value === "constructor")) {
-        if (hadConstructor) this$1.raise(key.start, "Duplicate constructor in the same class")
-        if (isGetSet) this$1.raise(key.start, "Constructor can't have get/set modifier")
-        if (isGenerator) this$1.raise(key.start, "Constructor can't be a generator")
-        if (isAsync) this$1.raise(key.start, "Constructor can't be an async method")
-        method.kind = "constructor"
-        hadConstructor = true
-      }
-    }
-    this$1.parseClassMethod(classBody, method, isGenerator, isAsync)
-    if (isGetSet) {
-      var paramCount = method.kind === "get" ? 0 : 1
-      if (method.value.params.length !== paramCount) {
-        var start = method.value.start
-        if (method.kind === "get")
-          this$1.raiseRecoverable(start, "getter should have no params")
-        else
-          this$1.raiseRecoverable(start, "setter should have exactly one param")
-      } else {
-        if (method.kind === "set" && method.value.params[0].type === "RestElement")
-          this$1.raiseRecoverable(method.value.params[0].start, "Setter cannot use rest params")
-      }
-    }
-  }
-  node.body = this.finishNode(classBody, "ClassBody")
-  return this.finishNode(node, isStatement ? "ClassDeclaration" : "ClassExpression")
-}
-
-pp$1.parseClassMethod = function(classBody, method, isGenerator, isAsync) {
-  method.value = this.parseMethod(isGenerator, isAsync)
-  classBody.body.push(this.finishNode(method, "MethodDefinition"))
-}
-
-pp$1.parseClassId = function(node, isStatement) {
-  node.id = this.type === tt.name ? this.parseIdent() : isStatement === true ? this.unexpected() : null
-}
-
-pp$1.parseClassSuper = function(node) {
-  node.superClass = this.eat(tt._extends) ? this.parseExprSubscripts() : null
-}
-
-// Parses module export declaration.
-
-pp$1.parseExport = function(node, exports) {
-  var this$1 = this;
-
-  this.next()
-  // export * from '...'
-  if (this.eat(tt.star)) {
-    this.expectContextual("from")
-    node.source = this.type === tt.string ? this.parseExprAtom() : this.unexpected()
-    this.semicolon()
-    return this.finishNode(node, "ExportAllDeclaration")
-  }
-  if (this.eat(tt._default)) { // export default ...
-    this.checkExport(exports, "default", this.lastTokStart)
-    var isAsync
-    if (this.type === tt._function || (isAsync = this.isAsyncFunction())) {
-      var fNode = this.startNode()
-      this.next()
-      if (isAsync) this.next()
-      node.declaration = this.parseFunction(fNode, "nullableID", false, isAsync)
-    } else if (this.type === tt._class) {
-      var cNode = this.startNode()
-      node.declaration = this.parseClass(cNode, "nullableID")
-    } else {
-      node.declaration = this.parseMaybeAssign()
-      this.semicolon()
-    }
-    return this.finishNode(node, "ExportDefaultDeclaration")
-  }
-  // export var|const|let|function|class ...
-  if (this.shouldParseExportStatement()) {
-    node.declaration = this.parseStatement(true)
-    if (node.declaration.type === "VariableDeclaration")
-      this.checkVariableExport(exports, node.declaration.declarations)
-    else
-      this.checkExport(exports, node.declaration.id.name, node.declaration.id.start)
-    node.specifiers = []
-    node.source = null
-  } else { // export { x, y as z } [from '...']
-    node.declaration = null
-    node.specifiers = this.parseExportSpecifiers(exports)
-    if (this.eatContextual("from")) {
-      node.source = this.type === tt.string ? this.parseExprAtom() : this.unexpected()
-    } else {
-      // check for keywords used as local names
-      for (var i = 0; i < node.specifiers.length; i++) {
-        if (this$1.keywords.test(node.specifiers[i].local.name) || this$1.reservedWords.test(node.specifiers[i].local.name)) {
-          this$1.unexpected(node.specifiers[i].local.start)
-        }
-      }
-
-      node.source = null
-    }
-    this.semicolon()
-  }
-  return this.finishNode(node, "ExportNamedDeclaration")
-}
-
-pp$1.checkExport = function(exports, name, pos) {
-  if (!exports) return
-  if (has(exports, name))
-    this.raiseRecoverable(pos, "Duplicate export '" + name + "'")
-  exports[name] = true
-}
-
-pp$1.checkPatternExport = function(exports, pat) {
-  var this$1 = this;
-
-  var type = pat.type
-  if (type == "Identifier")
-    this.checkExport(exports, pat.name, pat.start)
-  else if (type == "ObjectPattern")
-    for (var i = 0; i < pat.properties.length; ++i)
-      this$1.checkPatternExport(exports, pat.properties[i].value)
-  else if (type == "ArrayPattern")
-    for (var i$1 = 0; i$1 < pat.elements.length; ++i$1) {
-      var elt = pat.elements[i$1]
-      if (elt) this$1.checkPatternExport(exports, elt)
-    }
-  else if (type == "AssignmentPattern")
-    this.checkPatternExport(exports, pat.left)
-  else if (type == "ParenthesizedExpression")
-    this.checkPatternExport(exports, pat.expression)
-}
-
-pp$1.checkVariableExport = function(exports, decls) {
-  var this$1 = this;
-
-  if (!exports) return
-  for (var i = 0; i < decls.length; i++)
-    this$1.checkPatternExport(exports, decls[i].id)
-}
-
-pp$1.shouldParseExportStatement = function() {
-  return this.type.keyword === "var" ||
-    this.type.keyword === "const" ||
-    this.type.keyword === "class" ||
-    this.type.keyword === "function" ||
-    this.isLet() ||
-    this.isAsyncFunction()
-}
-
-// Parses a comma-separated list of module exports.
-
-pp$1.parseExportSpecifiers = function(exports) {
-  var this$1 = this;
-
-  var nodes = [], first = true
-  // export { x, y as z } [from '...']
-  this.expect(tt.braceL)
-  while (!this.eat(tt.braceR)) {
-    if (!first) {
-      this$1.expect(tt.comma)
-      if (this$1.afterTrailingComma(tt.braceR)) break
-    } else first = false
-
-    var node = this$1.startNode()
-    node.local = this$1.parseIdent(true)
-    node.exported = this$1.eatContextual("as") ? this$1.parseIdent(true) : node.local
-    this$1.checkExport(exports, node.exported.name, node.exported.start)
-    nodes.push(this$1.finishNode(node, "ExportSpecifier"))
-  }
-  return nodes
-}
-
-// Parses import declaration.
-
-pp$1.parseImport = function(node) {
-  this.next()
-  // import '...'
-  if (this.type === tt.string) {
-    node.specifiers = empty
-    node.source = this.parseExprAtom()
-  } else {
-    node.specifiers = this.parseImportSpecifiers()
-    this.expectContextual("from")
-    node.source = this.type === tt.string ? this.parseExprAtom() : this.unexpected()
-  }
-  this.semicolon()
-  return this.finishNode(node, "ImportDeclaration")
-}
-
-// Parses a comma-separated list of module imports.
-
-pp$1.parseImportSpecifiers = function() {
-  var this$1 = this;
-
-  var nodes = [], first = true
-  if (this.type === tt.name) {
-    // import defaultObj, { x, y as z } from '...'
-    var node = this.startNode()
-    node.local = this.parseIdent()
-    this.checkLVal(node.local, "let")
-    nodes.push(this.finishNode(node, "ImportDefaultSpecifier"))
-    if (!this.eat(tt.comma)) return nodes
-  }
-  if (this.type === tt.star) {
-    var node$1 = this.startNode()
-    this.next()
-    this.expectContextual("as")
-    node$1.local = this.parseIdent()
-    this.checkLVal(node$1.local, "let")
-    nodes.push(this.finishNode(node$1, "ImportNamespaceSpecifier"))
-    return nodes
-  }
-  this.expect(tt.braceL)
-  while (!this.eat(tt.braceR)) {
-    if (!first) {
-      this$1.expect(tt.comma)
-      if (this$1.afterTrailingComma(tt.braceR)) break
-    } else first = false
-
-    var node$2 = this$1.startNode()
-    node$2.imported = this$1.parseIdent(true)
-    if (this$1.eatContextual("as")) {
-      node$2.local = this$1.parseIdent()
-    } else {
-      node$2.local = node$2.imported
-      if (this$1.isKeyword(node$2.local.name)) this$1.unexpected(node$2.local.start)
-      if (this$1.reservedWordsStrict.test(node$2.local.name)) this$1.raiseRecoverable(node$2.local.start, "The keyword '" + node$2.local.name + "' is reserved")
-    }
-    this$1.checkLVal(node$2.local, "let")
-    nodes.push(this$1.finishNode(node$2, "ImportSpecifier"))
-  }
-  return nodes
-}
-
-var pp$2 = Parser.prototype
-
-// Convert existing expression atom to assignable pattern
-// if possible.
-
-pp$2.toAssignable = function(node, isBinding) {
-  var this$1 = this;
-
-  if (this.options.ecmaVersion >= 6 && node) {
-    switch (node.type) {
-    case "Identifier":
-      if (this.inAsync && node.name === "await")
-        this.raise(node.start, "Can not use 'await' as identifier inside an async function")
-      break
-
-    case "ObjectPattern":
-    case "ArrayPattern":
-      break
-
-    case "ObjectExpression":
-      node.type = "ObjectPattern"
-      for (var i = 0; i < node.properties.length; i++) {
-        var prop = node.properties[i]
-        if (prop.kind !== "init") this$1.raise(prop.key.start, "Object pattern can't contain getter or setter")
-        this$1.toAssignable(prop.value, isBinding)
-      }
-      break
-
-    case "ArrayExpression":
-      node.type = "ArrayPattern"
-      this.toAssignableList(node.elements, isBinding)
-      break
-
-    case "AssignmentExpression":
-      if (node.operator === "=") {
-        node.type = "AssignmentPattern"
-        delete node.operator
-        this.toAssignable(node.left, isBinding)
-        // falls through to AssignmentPattern
-      } else {
-        this.raise(node.left.end, "Only '=' operator can be used for specifying default value.")
-        break
-      }
-
-    case "AssignmentPattern":
-      break
-
-    case "ParenthesizedExpression":
-      node.expression = this.toAssignable(node.expression, isBinding)
-      break
-
-    case "MemberExpression":
-      if (!isBinding) break
-
-    default:
-      this.raise(node.start, "Assigning to rvalue")
-    }
-  }
-  return node
-}
-
-// Convert list of expression atoms to binding list.
-
-pp$2.toAssignableList = function(exprList, isBinding) {
-  var this$1 = this;
-
-  var end = exprList.length
-  if (end) {
-    var last = exprList[end - 1]
-    if (last && last.type == "RestElement") {
-      --end
-    } else if (last && last.type == "SpreadElement") {
-      last.type = "RestElement"
-      var arg = last.argument
-      this.toAssignable(arg, isBinding)
-      if (arg.type !== "Identifier" && arg.type !== "MemberExpression" && arg.type !== "ArrayPattern")
-        this.unexpected(arg.start)
-      --end
-    }
-
-    if (isBinding && last && last.type === "RestElement" && last.argument.type !== "Identifier")
-      this.unexpected(last.argument.start)
-  }
-  for (var i = 0; i < end; i++) {
-    var elt = exprList[i]
-    if (elt) this$1.toAssignable(elt, isBinding)
-  }
-  return exprList
-}
-
-// Parses spread element.
-
-pp$2.parseSpread = function(refDestructuringErrors) {
-  var node = this.startNode()
-  this.next()
-  node.argument = this.parseMaybeAssign(false, refDestructuringErrors)
-  return this.finishNode(node, "SpreadElement")
-}
-
-pp$2.parseRest = function(allowNonIdent) {
-  var node = this.startNode()
-  this.next()
-
-  // RestElement inside of a function parameter must be an identifier
-  if (allowNonIdent) node.argument = this.type === tt.name ? this.parseIdent() : this.unexpected()
-  else node.argument = this.type === tt.name || this.type === tt.bracketL ? this.parseBindingAtom() : this.unexpected()
-
-  return this.finishNode(node, "RestElement")
-}
-
-// Parses lvalue (assignable) atom.
-
-pp$2.parseBindingAtom = function() {
-  if (this.options.ecmaVersion < 6) return this.parseIdent()
-  switch (this.type) {
-  case tt.name:
-    return this.parseIdent()
-
-  case tt.bracketL:
-    var node = this.startNode()
-    this.next()
-    node.elements = this.parseBindingList(tt.bracketR, true, true)
-    return this.finishNode(node, "ArrayPattern")
-
-  case tt.braceL:
-    return this.parseObj(true)
-
-  default:
-    this.unexpected()
-  }
-}
-
-pp$2.parseBindingList = function(close, allowEmpty, allowTrailingComma, allowNonIdent) {
-  var this$1 = this;
-
-  var elts = [], first = true
-  while (!this.eat(close)) {
-    if (first) first = false
-    else this$1.expect(tt.comma)
-    if (allowEmpty && this$1.type === tt.comma) {
-      elts.push(null)
-    } else if (allowTrailingComma && this$1.afterTrailingComma(close)) {
-      break
-    } else if (this$1.type === tt.ellipsis) {
-      var rest = this$1.parseRest(allowNonIdent)
-      this$1.parseBindingListItem(rest)
-      elts.push(rest)
-      if (this$1.type === tt.comma) this$1.raise(this$1.start, "Comma is not permitted after the rest element")
-      this$1.expect(close)
-      break
-    } else {
-      var elem = this$1.parseMaybeDefault(this$1.start, this$1.startLoc)
-      this$1.parseBindingListItem(elem)
-      elts.push(elem)
-    }
-  }
-  return elts
-}
-
-pp$2.parseBindingListItem = function(param) {
-  return param
-}
-
-// Parses assignment pattern around given atom if possible.
-
-pp$2.parseMaybeDefault = function(startPos, startLoc, left) {
-  left = left || this.parseBindingAtom()
-  if (this.options.ecmaVersion < 6 || !this.eat(tt.eq)) return left
-  var node = this.startNodeAt(startPos, startLoc)
-  node.left = left
-  node.right = this.parseMaybeAssign()
-  return this.finishNode(node, "AssignmentPattern")
-}
-
-// Verify that a node is an lval — something that can be assigned
-// to.
-// bindingType can be either:
-// 'var' indicating that the lval creates a 'var' binding
-// 'let' indicating that the lval creates a lexical ('let' or 'const') binding
-// 'none' indicating that the binding should be checked for illegal identifiers, but not for duplicate references
-
-pp$2.checkLVal = function(expr, bindingType, checkClashes) {
-  var this$1 = this;
-
-  switch (expr.type) {
-  case "Identifier":
-    if (this.strict && this.reservedWordsStrictBind.test(expr.name))
-      this.raiseRecoverable(expr.start, (bindingType ? "Binding " : "Assigning to ") + expr.name + " in strict mode")
-    if (checkClashes) {
-      if (has(checkClashes, expr.name))
-        this.raiseRecoverable(expr.start, "Argument name clash")
-      checkClashes[expr.name] = true
-    }
-    if (bindingType && bindingType !== "none") {
-      if (
-        bindingType === "var" && !this.canDeclareVarName(expr.name) ||
-        bindingType !== "var" && !this.canDeclareLexicalName(expr.name)
-      ) {
-        this.raiseRecoverable(expr.start, ("Identifier '" + (expr.name) + "' has already been declared"))
-      }
-      if (bindingType === "var") {
-        this.declareVarName(expr.name)
-      } else {
-        this.declareLexicalName(expr.name)
-      }
-    }
-    break
-
-  case "MemberExpression":
-    if (bindingType) this.raiseRecoverable(expr.start, (bindingType ? "Binding" : "Assigning to") + " member expression")
-    break
-
-  case "ObjectPattern":
-    for (var i = 0; i < expr.properties.length; i++)
-      this$1.checkLVal(expr.properties[i].value, bindingType, checkClashes)
-    break
-
-  case "ArrayPattern":
-    for (var i$1 = 0; i$1 < expr.elements.length; i$1++) {
-      var elem = expr.elements[i$1]
-      if (elem) this$1.checkLVal(elem, bindingType, checkClashes)
-    }
-    break
-
-  case "AssignmentPattern":
-    this.checkLVal(expr.left, bindingType, checkClashes)
-    break
-
-  case "RestElement":
-    this.checkLVal(expr.argument, bindingType, checkClashes)
-    break
-
-  case "ParenthesizedExpression":
-    this.checkLVal(expr.expression, bindingType, checkClashes)
-    break
-
-  default:
-    this.raise(expr.start, (bindingType ? "Binding" : "Assigning to") + " rvalue")
-  }
-}
-
-// 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
-
-var pp$3 = Parser.prototype
-
-// Check if property name clashes with already added.
-// Object/class 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.
-
-pp$3.checkPropClash = function(prop, propHash) {
-  if (this.options.ecmaVersion >= 6 && (prop.computed || prop.method || prop.shorthand))
-    return
-  var key = prop.key;
-  var name
-  switch (key.type) {
-  case "Identifier": name = key.name; break
-  case "Literal": name = String(key.value); break
-  default: return
-  }
-  var kind = prop.kind;
-  if (this.options.ecmaVersion >= 6) {
-    if (name === "__proto__" && kind === "init") {
-      if (propHash.proto) this.raiseRecoverable(key.start, "Redefinition of __proto__ property")
-      propHash.proto = true
-    }
-    return
-  }
-  name = "$" + name
-  var other = propHash[name]
-  if (other) {
-    var redefinition
-    if (kind === "init") {
-      redefinition = this.strict && other.init || other.get || other.set
-    } else {
-      redefinition = other.init || other[kind]
-    }
-    if (redefinition)
-      this.raiseRecoverable(key.start, "Redefinition of property")
-  } else {
-    other = propHash[name] = {
-      init: false,
-      get: false,
-      set: false
-    }
-  }
-  other[kind] = true
-}
-
-// ### 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 optional arguments are used to
-// forbid the `in` operator (in for loops initalization expressions)
-// and provide reference for storing '=' operator inside shorthand
-// property assignment in contexts where both object expression
-// and object pattern might appear (so it's possible to raise
-// delayed syntax error at correct position).
-
-pp$3.parseExpression = function(noIn, refDestructuringErrors) {
-  var this$1 = this;
-
-  var startPos = this.start, startLoc = this.startLoc
-  var expr = this.parseMaybeAssign(noIn, refDestructuringErrors)
-  if (this.type === tt.comma) {
-    var node = this.startNodeAt(startPos, startLoc)
-    node.expressions = [expr]
-    while (this.eat(tt.comma)) node.expressions.push(this$1.parseMaybeAssign(noIn, refDestructuringErrors))
-    return this.finishNode(node, "SequenceExpression")
-  }
-  return expr
-}
-
-// Parse an assignment expression. This includes applications of
-// operators like `+=`.
-
-pp$3.parseMaybeAssign = function(noIn, refDestructuringErrors, afterLeftParse) {
-  if (this.inGenerator && this.isContextual("yield")) return this.parseYield()
-
-  var ownDestructuringErrors = false, oldParenAssign = -1, oldTrailingComma = -1
-  if (refDestructuringErrors) {
-    oldParenAssign = refDestructuringErrors.parenthesizedAssign
-    oldTrailingComma = refDestructuringErrors.trailingComma
-    refDestructuringErrors.parenthesizedAssign = refDestructuringErrors.trailingComma = -1
-  } else {
-    refDestructuringErrors = new DestructuringErrors
-    ownDestructuringErrors = true
-  }
-
-  var startPos = this.start, startLoc = this.startLoc
-  if (this.type == tt.parenL || this.type == tt.name)
-    this.potentialArrowAt = this.start
-  var left = this.parseMaybeConditional(noIn, refDestructuringErrors)
-  if (afterLeftParse) left = afterLeftParse.call(this, left, startPos, startLoc)
-  if (this.type.isAssign) {
-    this.checkPatternErrors(refDestructuringErrors, true)
-    if (!ownDestructuringErrors) DestructuringErrors.call(refDestructuringErrors)
-    var node = this.startNodeAt(startPos, startLoc)
-    node.operator = this.value
-    node.left = this.type === tt.eq ? this.toAssignable(left) : left
-    refDestructuringErrors.shorthandAssign = -1 // reset because shorthand default was used correctly
-    this.checkLVal(left)
-    this.next()
-    node.right = this.parseMaybeAssign(noIn)
-    return this.finishNode(node, "AssignmentExpression")
-  } else {
-    if (ownDestructuringErrors) this.checkExpressionErrors(refDestructuringErrors, true)
-  }
-  if (oldParenAssign > -1) refDestructuringErrors.parenthesizedAssign = oldParenAssign
-  if (oldTrailingComma > -1) refDestructuringErrors.trailingComma = oldTrailingComma
-  return left
-}
-
-// Parse a ternary conditional (`?:`) operator.
-
-pp$3.parseMaybeConditional = function(noIn, refDestructuringErrors) {
-  var startPos = this.start, startLoc = this.startLoc
-  var expr = this.parseExprOps(noIn, refDestructuringErrors)
-  if (this.checkExpressionErrors(refDestructuringErrors)) return expr
-  if (this.eat(tt.question)) {
-    var node = this.startNodeAt(startPos, startLoc)
-    node.test = expr
-    node.consequent = this.parseMaybeAssign()
-    this.expect(tt.colon)
-    node.alternate = this.parseMaybeAssign(noIn)
-    return this.finishNode(node, "ConditionalExpression")
-  }
-  return expr
-}
-
-// Start the precedence parser.
-
-pp$3.parseExprOps = function(noIn, refDestructuringErrors) {
-  var startPos = this.start, startLoc = this.startLoc
-  var expr = this.parseMaybeUnary(refDestructuringErrors, false)
-  if (this.checkExpressionErrors(refDestructuringErrors)) return expr
-  return expr.start == startPos && expr.type === "ArrowFunctionExpression" ? expr : this.parseExprOp(expr, startPos, startLoc, -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.
-
-pp$3.parseExprOp = function(left, leftStartPos, leftStartLoc, minPrec, noIn) {
-  var prec = this.type.binop
-  if (prec != null && (!noIn || this.type !== tt._in)) {
-    if (prec > minPrec) {
-      var logical = this.type === tt.logicalOR || this.type === tt.logicalAND
-      var op = this.value
-      this.next()
-      var startPos = this.start, startLoc = this.startLoc
-      var right = this.parseExprOp(this.parseMaybeUnary(null, false), startPos, startLoc, prec, noIn)
-      var node = this.buildBinary(leftStartPos, leftStartLoc, left, right, op, logical)
-      return this.parseExprOp(node, leftStartPos, leftStartLoc, minPrec, noIn)
-    }
-  }
-  return left
-}
-
-pp$3.buildBinary = function(startPos, startLoc, left, right, op, logical) {
-  var node = this.startNodeAt(startPos, startLoc)
-  node.left = left
-  node.operator = op
-  node.right = right
-  return this.finishNode(node, logical ? "LogicalExpression" : "BinaryExpression")
-}
-
-// Parse unary operators, both prefix and postfix.
-
-pp$3.parseMaybeUnary = function(refDestructuringErrors, sawUnary) {
-  var this$1 = this;
-
-  var startPos = this.start, startLoc = this.startLoc, expr
-  if (this.inAsync && this.isContextual("await")) {
-    expr = this.parseAwait(refDestructuringErrors)
-    sawUnary = true
-  } else if (this.type.prefix) {
-    var node = this.startNode(), update = this.type === tt.incDec
-    node.operator = this.value
-    node.prefix = true
-    this.next()
-    node.argument = this.parseMaybeUnary(null, true)
-    this.checkExpressionErrors(refDestructuringErrors, true)
-    if (update) this.checkLVal(node.argument)
-    else if (this.strict && node.operator === "delete" &&
-             node.argument.type === "Identifier")
-      this.raiseRecoverable(node.start, "Deleting local variable in strict mode")
-    else sawUnary = true
-    expr = this.finishNode(node, update ? "UpdateExpression" : "UnaryExpression")
-  } else {
-    expr = this.parseExprSubscripts(refDestructuringErrors)
-    if (this.checkExpressionErrors(refDestructuringErrors)) return expr
-    while (this.type.postfix && !this.canInsertSemicolon()) {
-      var node$1 = this$1.startNodeAt(startPos, startLoc)
-      node$1.operator = this$1.value
-      node$1.prefix = false
-      node$1.argument = expr
-      this$1.checkLVal(expr)
-      this$1.next()
-      expr = this$1.finishNode(node$1, "UpdateExpression")
-    }
-  }
-
-  if (!sawUnary && this.eat(tt.starstar))
-    return this.buildBinary(startPos, startLoc, expr, this.parseMaybeUnary(null, false), "**", false)
-  else
-    return expr
-}
-
-// Parse call, dot, and `[]`-subscript expressions.
-
-pp$3.parseExprSubscripts = function(refDestructuringErrors) {
-  var startPos = this.start, startLoc = this.startLoc
-  var expr = this.parseExprAtom(refDestructuringErrors)
-  var skipArrowSubscripts = expr.type === "ArrowFunctionExpression" && this.input.slice(this.lastTokStart, this.lastTokEnd) !== ")"
-  if (this.checkExpressionErrors(refDestructuringErrors) || skipArrowSubscripts) return expr
-  var result = this.parseSubscripts(expr, startPos, startLoc)
-  if (refDestructuringErrors && result.type === "MemberExpression") {
-    if (refDestructuringErrors.parenthesizedAssign >= result.start) refDestructuringErrors.parenthesizedAssign = -1
-    if (refDestructuringErrors.parenthesizedBind >= result.start) refDestructuringErrors.parenthesizedBind = -1
-  }
-  return result
-}
-
-pp$3.parseSubscripts = function(base, startPos, startLoc, noCalls) {
-  var this$1 = this;
-
-  var maybeAsyncArrow = this.options.ecmaVersion >= 8 && base.type === "Identifier" && base.name === "async" &&
-      this.lastTokEnd == base.end && !this.canInsertSemicolon()
-  for (var computed;;) {
-    if ((computed = this$1.eat(tt.bracketL)) || this$1.eat(tt.dot)) {
-      var node = this$1.startNodeAt(startPos, startLoc)
-      node.object = base
-      node.property = computed ? this$1.parseExpression() : this$1.parseIdent(true)
-      node.computed = !!computed
-      if (computed) this$1.expect(tt.bracketR)
-      base = this$1.finishNode(node, "MemberExpression")
-    } else if (!noCalls && this$1.eat(tt.parenL)) {
-      var refDestructuringErrors = new DestructuringErrors, oldYieldPos = this$1.yieldPos, oldAwaitPos = this$1.awaitPos
-      this$1.yieldPos = 0
-      this$1.awaitPos = 0
-      var exprList = this$1.parseExprList(tt.parenR, this$1.options.ecmaVersion >= 8, false, refDestructuringErrors)
-      if (maybeAsyncArrow && !this$1.canInsertSemicolon() && this$1.eat(tt.arrow)) {
-        this$1.checkPatternErrors(refDestructuringErrors, false)
-        this$1.checkYieldAwaitInDefaultParams()
-        this$1.yieldPos = oldYieldPos
-        this$1.awaitPos = oldAwaitPos
-        return this$1.parseArrowExpression(this$1.startNodeAt(startPos, startLoc), exprList, true)
-      }
-      this$1.checkExpressionErrors(refDestructuringErrors, true)
-      this$1.yieldPos = oldYieldPos || this$1.yieldPos
-      this$1.awaitPos = oldAwaitPos || this$1.awaitPos
-      var node$1 = this$1.startNodeAt(startPos, startLoc)
-      node$1.callee = base
-      node$1.arguments = exprList
-      base = this$1.finishNode(node$1, "CallExpression")
-    } else if (this$1.type === tt.backQuote) {
-      var node$2 = this$1.startNodeAt(startPos, startLoc)
-      node$2.tag = base
-      node$2.quasi = this$1.parseTemplate()
-      base = this$1.finishNode(node$2, "TaggedTemplateExpression")
-    } 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 `{}`.
-
-pp$3.parseExprAtom = function(refDestructuringErrors) {
-  var node, canBeArrow = this.potentialArrowAt == this.start
-  switch (this.type) {
-  case tt._super:
-    if (!this.inFunction)
-      this.raise(this.start, "'super' outside of function or class")
-
-  case tt._this:
-    var type = this.type === tt._this ? "ThisExpression" : "Super"
-    node = this.startNode()
-    this.next()
-    return this.finishNode(node, type)
-
-  case tt.name:
-    var startPos = this.start, startLoc = this.startLoc
-    var id = this.parseIdent(this.type !== tt.name)
-    if (this.options.ecmaVersion >= 8 && id.name === "async" && !this.canInsertSemicolon() && this.eat(tt._function))
-      return this.parseFunction(this.startNodeAt(startPos, startLoc), false, false, true)
-    if (canBeArrow && !this.canInsertSemicolon()) {
-      if (this.eat(tt.arrow))
-        return this.parseArrowExpression(this.startNodeAt(startPos, startLoc), [id], false)
-      if (this.options.ecmaVersion >= 8 && id.name === "async" && this.type === tt.name) {
-        id = this.parseIdent()
-        if (this.canInsertSemicolon() || !this.eat(tt.arrow))
-          this.unexpected()
-        return this.parseArrowExpression(this.startNodeAt(startPos, startLoc), [id], true)
-      }
-    }
-    return id
-
-  case tt.regexp:
-    var value = this.value
-    node = this.parseLiteral(value.value)
-    node.regex = {pattern: value.pattern, flags: value.flags}
-    return node
-
-  case tt.num: case tt.string:
-    return this.parseLiteral(this.value)
-
-  case tt._null: case tt._true: case tt._false:
-    node = this.startNode()
-    node.value = this.type === tt._null ? null : this.type === tt._true
-    node.raw = this.type.keyword
-    this.next()
-    return this.finishNode(node, "Literal")
-
-  case tt.parenL:
-    var start = this.start, expr = this.parseParenAndDistinguishExpression(canBeArrow)
-    if (refDestructuringErrors) {
-      if (refDestructuringErrors.parenthesizedAssign < 0 && !this.isSimpleAssignTarget(expr))
-        refDestructuringErrors.parenthesizedAssign = start
-      if (refDestructuringErrors.parenthesizedBind < 0)
-        refDestructuringErrors.parenthesizedBind = start
-    }
-    return expr
-
-  case tt.bracketL:
-    node = this.startNode()
-    this.next()
-    node.elements = this.parseExprList(tt.bracketR, true, true, refDestructuringErrors)
-    return this.finishNode(node, "ArrayExpression")
-
-  case tt.braceL:
-    return this.parseObj(false, refDestructuringErrors)
-
-  case tt._function:
-    node = this.startNode()
-    this.next()
-    return this.parseFunction(node, false)
-
-  case tt._class:
-    return this.parseClass(this.startNode(), false)
-
-  case tt._new:
-    return this.parseNew()
-
-  case tt.backQuote:
-    return this.parseTemplate()
-
-  default:
-    this.unexpected()
-  }
-}
-
-pp$3.parseLiteral = function(value) {
-  var node = this.startNode()
-  node.value = value
-  node.raw = this.input.slice(this.start, this.end)
-  this.next()
-  return this.finishNode(node, "Literal")
-}
-
-pp$3.parseParenExpression = function() {
-  this.expect(tt.parenL)
-  var val = this.parseExpression()
-  this.expect(tt.parenR)
-  return val
-}
-
-pp$3.parseParenAndDistinguishExpression = function(canBeArrow) {
-  var this$1 = this;
-
-  var startPos = this.start, startLoc = this.startLoc, val, allowTrailingComma = this.options.ecmaVersion >= 8
-  if (this.options.ecmaVersion >= 6) {
-    this.next()
-
-    var innerStartPos = this.start, innerStartLoc = this.startLoc
-    var exprList = [], first = true, lastIsComma = false
-    var refDestructuringErrors = new DestructuringErrors, oldYieldPos = this.yieldPos, oldAwaitPos = this.awaitPos, spreadStart, innerParenStart
-    this.yieldPos = 0
-    this.awaitPos = 0
-    while (this.type !== tt.parenR) {
-      first ? first = false : this$1.expect(tt.comma)
-      if (allowTrailingComma && this$1.afterTrailingComma(tt.parenR, true)) {
-        lastIsComma = true
-        break
-      } else if (this$1.type === tt.ellipsis) {
-        spreadStart = this$1.start
-        exprList.push(this$1.parseParenItem(this$1.parseRest()))
-        if (this$1.type === tt.comma) this$1.raise(this$1.start, "Comma is not permitted after the rest element")
-        break
-      } else {
-        if (this$1.type === tt.parenL && !innerParenStart) {
-          innerParenStart = this$1.start
-        }
-        exprList.push(this$1.parseMaybeAssign(false, refDestructuringErrors, this$1.parseParenItem))
-      }
-    }
-    var innerEndPos = this.start, innerEndLoc = this.startLoc
-    this.expect(tt.parenR)
-
-    if (canBeArrow && !this.canInsertSemicolon() && this.eat(tt.arrow)) {
-      this.checkPatternErrors(refDestructuringErrors, false)
-      this.checkYieldAwaitInDefaultParams()
-      if (innerParenStart) this.unexpected(innerParenStart)
-      this.yieldPos = oldYieldPos
-      this.awaitPos = oldAwaitPos
-      return this.parseParenArrowList(startPos, startLoc, exprList)
-    }
-
-    if (!exprList.length || lastIsComma) this.unexpected(this.lastTokStart)
-    if (spreadStart) this.unexpected(spreadStart)
-    this.checkExpressionErrors(refDestructuringErrors, true)
-    this.yieldPos = oldYieldPos || this.yieldPos
-    this.awaitPos = oldAwaitPos || this.awaitPos
-
-    if (exprList.length > 1) {
-      val = this.startNodeAt(innerStartPos, innerStartLoc)
-      val.expressions = exprList
-      this.finishNodeAt(val, "SequenceExpression", innerEndPos, innerEndLoc)
-    } else {
-      val = exprList[0]
-    }
-  } else {
-    val = this.parseParenExpression()
-  }
-
-  if (this.options.preserveParens) {
-    var par = this.startNodeAt(startPos, startLoc)
-    par.expression = val
-    return this.finishNode(par, "ParenthesizedExpression")
-  } else {
-    return val
-  }
-}
-
-pp$3.parseParenItem = function(item) {
-  return item
-}
-
-pp$3.parseParenArrowList = function(startPos, startLoc, exprList) {
-  return this.parseArrowExpression(this.startNodeAt(startPos, startLoc), exprList)
-}
-
-// 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 noCalls
-// argument to parseSubscripts to prevent it from consuming the
-// argument list.
-
-var empty$1 = []
-
-pp$3.parseNew = function() {
-  var node = this.startNode()
-  var meta = this.parseIdent(true)
-  if (this.options.ecmaVersion >= 6 && this.eat(tt.dot)) {
-    node.meta = meta
-    node.property = this.parseIdent(true)
-    if (node.property.name !== "target")
-      this.raiseRecoverable(node.property.start, "The only valid meta property for new is new.target")
-    if (!this.inFunction)
-      this.raiseRecoverable(node.start, "new.target can only be used in functions")
-    return this.finishNode(node, "MetaProperty")
-  }
-  var startPos = this.start, startLoc = this.startLoc
-  node.callee = this.parseSubscripts(this.parseExprAtom(), startPos, startLoc, true)
-  if (this.eat(tt.parenL)) node.arguments = this.parseExprList(tt.parenR, this.options.ecmaVersion >= 8, false)
-  else node.arguments = empty$1
-  return this.finishNode(node, "NewExpression")
-}
-
-// Parse template expression.
-
-pp$3.parseTemplateElement = function() {
-  var elem = this.startNode()
-  elem.value = {
-    raw: this.input.slice(this.start, this.end).replace(/\r\n?/g, "\n"),
-    cooked: this.value
-  }
-  this.next()
-  elem.tail = this.type === tt.backQuote
-  return this.finishNode(elem, "TemplateElement")
-}
-
-pp$3.parseTemplate = function() {
-  var this$1 = this;
-
-  var node = this.startNode()
-  this.next()
-  node.expressions = []
-  var curElt = this.parseTemplateElement()
-  node.quasis = [curElt]
-  while (!curElt.tail) {
-    this$1.expect(tt.dollarBraceL)
-    node.expressions.push(this$1.parseExpression())
-    this$1.expect(tt.braceR)
-    node.quasis.push(curElt = this$1.parseTemplateElement())
-  }
-  this.next()
-  return this.finishNode(node, "TemplateLiteral")
-}
-
-// Parse an object literal or binding pattern.
-
-pp$3.parseObj = function(isPattern, refDestructuringErrors) {
-  var this$1 = this;
-
-  var node = this.startNode(), first = true, propHash = {}
-  node.properties = []
-  this.next()
-  while (!this.eat(tt.braceR)) {
-    if (!first) {
-      this$1.expect(tt.comma)
-      if (this$1.afterTrailingComma(tt.braceR)) break
-    } else first = false
-
-    var prop = this$1.startNode(), isGenerator, isAsync, startPos, startLoc
-    if (this$1.options.ecmaVersion >= 6) {
-      prop.method = false
-      prop.shorthand = false
-      if (isPattern || refDestructuringErrors) {
-        startPos = this$1.start
-        startLoc = this$1.startLoc
-      }
-      if (!isPattern)
-        isGenerator = this$1.eat(tt.star)
-    }
-    this$1.parsePropertyName(prop)
-    if (!isPattern && this$1.options.ecmaVersion >= 8 && !isGenerator && !prop.computed &&
-        prop.key.type === "Identifier" && prop.key.name === "async" && this$1.type !== tt.parenL &&
-        this$1.type !== tt.colon && !this$1.canInsertSemicolon()) {
-      isAsync = true
-      this$1.parsePropertyName(prop, refDestructuringErrors)
-    } else {
-      isAsync = false
-    }
-    this$1.parsePropertyValue(prop, isPattern, isGenerator, isAsync, startPos, startLoc, refDestructuringErrors)
-    this$1.checkPropClash(prop, propHash)
-    node.properties.push(this$1.finishNode(prop, "Property"))
-  }
-  return this.finishNode(node, isPattern ? "ObjectPattern" : "ObjectExpression")
-}
-
-pp$3.parsePropertyValue = function(prop, isPattern, isGenerator, isAsync, startPos, startLoc, refDestructuringErrors) {
-  if ((isGenerator || isAsync) && this.type === tt.colon)
-    this.unexpected()
-
-  if (this.eat(tt.colon)) {
-    prop.value = isPattern ? this.parseMaybeDefault(this.start, this.startLoc) : this.parseMaybeAssign(false, refDestructuringErrors)
-    prop.kind = "init"
-  } else if (this.options.ecmaVersion >= 6 && this.type === tt.parenL) {
-    if (isPattern) this.unexpected()
-    prop.kind = "init"
-    prop.method = true
-    prop.value = this.parseMethod(isGenerator, isAsync)
-  } else if (this.options.ecmaVersion >= 5 && !prop.computed && prop.key.type === "Identifier" &&
-             (prop.key.name === "get" || prop.key.name === "set") &&
-             (this.type != tt.comma && this.type != tt.braceR)) {
-    if (isGenerator || isAsync || isPattern) this.unexpected()
-    prop.kind = prop.key.name
-    this.parsePropertyName(prop)
-    prop.value = this.parseMethod(false)
-    var paramCount = prop.kind === "get" ? 0 : 1
-    if (prop.value.params.length !== paramCount) {
-      var start = prop.value.start
-      if (prop.kind === "get")
-        this.raiseRecoverable(start, "getter should have no params")
-      else
-        this.raiseRecoverable(start, "setter should have exactly one param")
-    } else {
-      if (prop.kind === "set" && prop.value.params[0].type === "RestElement")
-        this.raiseRecoverable(prop.value.params[0].start, "Setter cannot use rest params")
-    }
-  } else if (this.options.ecmaVersion >= 6 && !prop.computed && prop.key.type === "Identifier") {
-    if (this.keywords.test(prop.key.name) ||
-        (this.strict ? this.reservedWordsStrict : this.reservedWords).test(prop.key.name) ||
-        (this.inGenerator && prop.key.name == "yield") ||
-        (this.inAsync && prop.key.name == "await"))
-      this.raiseRecoverable(prop.key.start, "'" + prop.key.name + "' can not be used as shorthand property")
-    prop.kind = "init"
-    if (isPattern) {
-      prop.value = this.parseMaybeDefault(startPos, startLoc, prop.key)
-    } else if (this.type === tt.eq && refDestructuringErrors) {
-      if (refDestructuringErrors.shorthandAssign < 0)
-        refDestructuringErrors.shorthandAssign = this.start
-      prop.value = this.parseMaybeDefault(startPos, startLoc, prop.key)
-    } else {
-      prop.value = prop.key
-    }
-    prop.shorthand = true
-  } else this.unexpected()
-}
-
-pp$3.parsePropertyName = function(prop) {
-  if (this.options.ecmaVersion >= 6) {
-    if (this.eat(tt.bracketL)) {
-      prop.computed = true
-      prop.key = this.parseMaybeAssign()
-      this.expect(tt.bracketR)
-      return prop.key
-    } else {
-      prop.computed = false
-    }
-  }
-  return prop.key = this.type === tt.num || this.type === tt.string ? this.parseExprAtom() : this.parseIdent(true)
-}
-
-// Initialize empty function node.
-
-pp$3.initFunction = function(node) {
-  node.id = null
-  if (this.options.ecmaVersion >= 6) {
-    node.generator = false
-    node.expression = false
-  }
-  if (this.options.ecmaVersion >= 8)
-    node.async = false
-}
-
-// Parse object or class method.
-
-pp$3.parseMethod = function(isGenerator, isAsync) {
-  var node = this.startNode(), oldInGen = this.inGenerator, oldInAsync = this.inAsync,
-      oldYieldPos = this.yieldPos, oldAwaitPos = this.awaitPos, oldInFunc = this.inFunction
-
-  this.initFunction(node)
-  if (this.options.ecmaVersion >= 6)
-    node.generator = isGenerator
-  if (this.options.ecmaVersion >= 8)
-    node.async = !!isAsync
-
-  this.inGenerator = node.generator
-  this.inAsync = node.async
-  this.yieldPos = 0
-  this.awaitPos = 0
-  this.inFunction = true
-  this.enterFunctionScope()
-
-  this.expect(tt.parenL)
-  node.params = this.parseBindingList(tt.parenR, false, this.options.ecmaVersion >= 8)
-  this.checkYieldAwaitInDefaultParams()
-  this.parseFunctionBody(node, false)
-
-  this.inGenerator = oldInGen
-  this.inAsync = oldInAsync
-  this.yieldPos = oldYieldPos
-  this.awaitPos = oldAwaitPos
-  this.inFunction = oldInFunc
-  return this.finishNode(node, "FunctionExpression")
-}
-
-// Parse arrow function expression with given parameters.
-
-pp$3.parseArrowExpression = function(node, params, isAsync) {
-  var oldInGen = this.inGenerator, oldInAsync = this.inAsync,
-      oldYieldPos = this.yieldPos, oldAwaitPos = this.awaitPos, oldInFunc = this.inFunction
-
-  this.enterFunctionScope()
-  this.initFunction(node)
-  if (this.options.ecmaVersion >= 8)
-    node.async = !!isAsync
-
-  this.inGenerator = false
-  this.inAsync = node.async
-  this.yieldPos = 0
-  this.awaitPos = 0
-  this.inFunction = true
-
-  node.params = this.toAssignableList(params, true)
-  this.parseFunctionBody(node, true)
-
-  this.inGenerator = oldInGen
-  this.inAsync = oldInAsync
-  this.yieldPos = oldYieldPos
-  this.awaitPos = oldAwaitPos
-  this.inFunction = oldInFunc
-  return this.finishNode(node, "ArrowFunctionExpression")
-}
-
-// Parse function body and check parameters.
-
-pp$3.parseFunctionBody = function(node, isArrowFunction) {
-  var isExpression = isArrowFunction && this.type !== tt.braceL
-  var oldStrict = this.strict, useStrict = false
-
-  if (isExpression) {
-    node.body = this.parseMaybeAssign()
-    node.expression = true
-    this.checkParams(node, false)
-  } else {
-    var nonSimple = this.options.ecmaVersion >= 7 && !this.isSimpleParamList(node.params)
-    if (!oldStrict || nonSimple) {
-      useStrict = this.strictDirective(this.end)
-      // 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 (useStrict && nonSimple)
-        this.raiseRecoverable(node.start, "Illegal 'use strict' directive in function with non-simple parameter list")
-    }
-    // Start a new scope with regard to labels and the `inFunction`
-    // flag (restore them to their old value afterwards).
-    var oldLabels = this.labels
-    this.labels = []
-    if (useStrict) this.strict = true
-
-    // Add the params to varDeclaredNames to ensure that an error is thrown
-    // if a let/const declaration in the function clashes with one of the params.
-    this.checkParams(node, !oldStrict && !useStrict && !isArrowFunction && this.isSimpleParamList(node.params))
-    node.body = this.parseBlock(false)
-    node.expression = false
-    this.labels = oldLabels
-  }
-  this.exitFunctionScope()
-
-  if (this.strict && node.id) {
-    // Ensure the function name isn't a forbidden identifier in strict mode, e.g. 'eval'
-    this.checkLVal(node.id, "none")
-  }
-  this.strict = oldStrict
-}
-
-pp$3.isSimpleParamList = function(params) {
-  for (var i = 0; i < params.length; i++)
-    if (params[i].type !== "Identifier") return false
-  return true
-}
-
-// Checks function params for various disallowed patterns such as using "eval"
-// or "arguments" and duplicate parameters.
-
-pp$3.checkParams = function(node, allowDuplicates) {
-  var this$1 = this;
-
-  var nameHash = {}
-  for (var i = 0; i < node.params.length; i++) this$1.checkLVal(node.params[i], "var", allowDuplicates ? null : nameHash)
-}
-
-// 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).
-
-pp$3.parseExprList = function(close, allowTrailingComma, allowEmpty, refDestructuringErrors) {
-  var this$1 = this;
-
-  var elts = [], first = true
-  while (!this.eat(close)) {
-    if (!first) {
-      this$1.expect(tt.comma)
-      if (allowTrailingComma && this$1.afterTrailingComma(close)) break
-    } else first = false
-
-    var elt
-    if (allowEmpty && this$1.type === tt.comma)
-      elt = null
-    else if (this$1.type === tt.ellipsis) {
-      elt = this$1.parseSpread(refDestructuringErrors)
-      if (refDestructuringErrors && this$1.type === tt.comma && refDestructuringErrors.trailingComma < 0)
-        refDestructuringErrors.trailingComma = this$1.start
-    } else {
-      elt = this$1.parseMaybeAssign(false, refDestructuringErrors)
-    }
-    elts.push(elt)
-  }
-  return elts
-}
-
-// Parse the next token as an identifier. If `liberal` is true (used
-// when parsing properties), it will also convert keywords into
-// identifiers.
-
-pp$3.parseIdent = function(liberal) {
-  var node = this.startNode()
-  if (liberal && this.options.allowReserved == "never") liberal = false
-  if (this.type === tt.name) {
-    if (!liberal && (this.strict ? this.reservedWordsStrict : this.reservedWords).test(this.value) &&
-        (this.options.ecmaVersion >= 6 ||
-         this.input.slice(this.start, this.end).indexOf("\\") == -1))
-      this.raiseRecoverable(this.start, "The keyword '" + this.value + "' is reserved")
-    if (this.inGenerator && this.value === "yield")
-      this.raiseRecoverable(this.start, "Can not use 'yield' as identifier inside a generator")
-    if (this.inAsync && this.value === "await")
-      this.raiseRecoverable(this.start, "Can not use 'await' as identifier inside an async function")
-    node.name = this.value
-  } else if (liberal && this.type.keyword) {
-    node.name = this.type.keyword
-  } else {
-    this.unexpected()
-  }
-  this.next()
-  return this.finishNode(node, "Identifier")
-}
-
-// Parses yield expression inside generator.
-
-pp$3.parseYield = function() {
-  if (!this.yieldPos) this.yieldPos = this.start
-
-  var node = this.startNode()
-  this.next()
-  if (this.type == tt.semi || this.canInsertSemicolon() || (this.type != tt.star && !this.type.startsExpr)) {
-    node.delegate = false
-    node.argument = null
-  } else {
-    node.delegate = this.eat(tt.star)
-    node.argument = this.parseMaybeAssign()
-  }
-  return this.finishNode(node, "YieldExpression")
-}
-
-pp$3.parseAwait = function() {
-  if (!this.awaitPos) this.awaitPos = this.start
-
-  var node = this.startNode()
-  this.next()
-  node.argument = this.parseMaybeUnary(null, true)
-  return this.finishNode(node, "AwaitExpression")
-}
-
-var pp$4 = Parser.prototype
-
-// 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.
-
-pp$4.raise = function(pos, message) {
-  var loc = getLineInfo(this.input, pos)
-  message += " (" + loc.line + ":" + loc.column + ")"
-  var err = new SyntaxError(message)
-  err.pos = pos; err.loc = loc; err.raisedAt = this.pos
-  throw err
-}
-
-pp$4.raiseRecoverable = pp$4.raise
-
-pp$4.curPosition = function() {
-  if (this.options.locations) {
-    return new Position(this.curLine, this.pos - this.lineStart)
-  }
-}
-
-var pp$5 = Parser.prototype
-
-// Object.assign polyfill
-var assign = Object.assign || function(target) {
-  var sources = [], len = arguments.length - 1;
-  while ( len-- > 0 ) sources[ len ] = arguments[ len + 1 ];
-
-  for (var i = 0; i < sources.length; i++) {
-    var source = sources[i]
-    for (var key in source) {
-      if (has(source, key)) {
-        target[key] = source[key]
-      }
-    }
-  }
-  return target
-}
-
-// The functions in this module keep track of declared variables in the current scope in order to detect duplicate variable names.
-
-pp$5.enterFunctionScope = function() {
-  // var: a hash of var-declared names in the current lexical scope
-  // lexical: a hash of lexically-declared names in the current lexical scope
-  // childVar: a hash of var-declared names in all child lexical scopes of the current lexical scope (within the current function scope)
-  // parentLexical: a hash of lexically-declared names in all parent lexical scopes of the current lexical scope (within the current function scope)
-  this.scopeStack.push({var: {}, lexical: {}, childVar: {}, parentLexical: {}})
-}
-
-pp$5.exitFunctionScope = function() {
-  this.scopeStack.pop()
-}
-
-pp$5.enterLexicalScope = function() {
-  var parentScope = this.scopeStack[this.scopeStack.length - 1]
-  var childScope = {var: {}, lexical: {}, childVar: {}, parentLexical: {}}
-
-  this.scopeStack.push(childScope)
-  assign(childScope.parentLexical, parentScope.lexical, parentScope.parentLexical)
-}
-
-pp$5.exitLexicalScope = function() {
-  var childScope = this.scopeStack.pop()
-  var parentScope = this.scopeStack[this.scopeStack.length - 1]
-
-  assign(parentScope.childVar, childScope.var, childScope.childVar)
-}
-
-/**
- * A name can be declared with `var` if there are no variables with the same name declared with `let`/`const`
- * in the current lexical scope or any of the parent lexical scopes in this function.
- */
-pp$5.canDeclareVarName = function(name) {
-  var currentScope = this.scopeStack[this.scopeStack.length - 1]
-
-  return !has(currentScope.lexical, name) && !has(currentScope.parentLexical, name)
-}
-
-/**
- * A name can be declared with `let`/`const` if there are no variables with the same name declared with `let`/`const`
- * in the current scope, and there are no variables with the same name declared with `var` in the current scope or in
- * any child lexical scopes in this function.
- */
-pp$5.canDeclareLexicalName = function(name) {
-  var currentScope = this.scopeStack[this.scopeStack.length - 1]
-
-  return !has(currentScope.lexical, name) && !has(currentScope.var, name) && !has(currentScope.childVar, name)
-}
-
-pp$5.declareVarName = function(name) {
-  this.scopeStack[this.scopeStack.length - 1].var[name] = true
-}
-
-pp$5.declareLexicalName = function(name) {
-  this.scopeStack[this.scopeStack.length - 1].lexical[name] = true
-}
-
-var Node = function Node(parser, pos, loc) {
-  this.type = ""
-  this.start = pos
-  this.end = 0
-  if (parser.options.locations)
-    this.loc = new SourceLocation(parser, loc)
-  if (parser.options.directSourceFile)
-    this.sourceFile = parser.options.directSourceFile
-  if (parser.options.ranges)
-    this.range = [pos, 0]
-};
-
-// Start an AST node, attaching a start offset.
-
-var pp$6 = Parser.prototype
-
-pp$6.startNode = function() {
-  return new Node(this, this.start, this.startLoc)
-}
-
-pp$6.startNodeAt = function(pos, loc) {
-  return new Node(this, pos, loc)
-}
-
-// Finish an AST node, adding `type` and `end` properties.
-
-function finishNodeAt(node, type, pos, loc) {
-  node.type = type
-  node.end = pos
-  if (this.options.locations)
-    node.loc.end = loc
-  if (this.options.ranges)
-    node.range[1] = pos
-  return node
-}
-
-pp$6.finishNode = function(node, type) {
-  return finishNodeAt.call(this, node, type, this.lastTokEnd, this.lastTokEndLoc)
-}
-
-// Finish node at given position
-
-pp$6.finishNodeAt = function(node, type, pos, loc) {
-  return finishNodeAt.call(this, node, type, pos, loc)
-}
-
-// The algorithm used to determine whether a regexp can appear at a
-// given point in the program is loosely based on sweet.js' approach.
-// See https://github.com/mozilla/sweet.js/wiki/design
-
-var TokContext = function TokContext(token, isExpr, preserveSpace, override, generator) {
-  this.token = token
-  this.isExpr = !!isExpr
-  this.preserveSpace = !!preserveSpace
-  this.override = override
-  this.generator = !!generator
-};
-
-var types = {
-  b_stat: new TokContext("{", false),
-  b_expr: new TokContext("{", true),
-  b_tmpl: new TokContext("${", true),
-  p_stat: new TokContext("(", false),
-  p_expr: new TokContext("(", true),
-  q_tmpl: new TokContext("`", true, true, function (p) { return p.readTmplToken(); }),
-  f_expr: new TokContext("function", true),
-  f_expr_gen: new TokContext("function", true, false, null, true),
-  f_gen: new TokContext("function", false, false, null, true)
-}
-
-var pp$7 = Parser.prototype
-
-pp$7.initialContext = function() {
-  return [types.b_stat]
-}
-
-pp$7.braceIsBlock = function(prevType) {
-  if (prevType === tt.colon) {
-    var parent = this.curContext()
-    if (parent === types.b_stat || parent === types.b_expr)
-      return !parent.isExpr
-  }
-  if (prevType === tt._return)
-    return lineBreak.test(this.input.slice(this.lastTokEnd, this.start))
-  if (prevType === tt._else || prevType === tt.semi || prevType === tt.eof || prevType === tt.parenR || prevType == tt.arrow)
-    return true
-  if (prevType == tt.braceL)
-    return this.curContext() === types.b_stat
-  return !this.exprAllowed
-}
-
-pp$7.inGeneratorContext = function() {
-  var this$1 = this;
-
-  for (var i = this.context.length - 1; i >= 0; i--)
-    if (this$1.context[i].generator) return true
-  return false
-}
-
-pp$7.updateContext = function(prevType) {
-  var update, type = this.type
-  if (type.keyword && prevType == tt.dot)
-    this.exprAllowed = false
-  else if (update = type.updateContext)
-    update.call(this, prevType)
-  else
-    this.exprAllowed = type.beforeExpr
-}
-
-// Token-specific context update code
-
-tt.parenR.updateContext = tt.braceR.updateContext = function() {
-  if (this.context.length == 1) {
-    this.exprAllowed = true
-    return
-  }
-  var out = this.context.pop(), cur
-  if (out === types.b_stat && (cur = this.curContext()) && cur.token === "function") {
-    this.context.pop()
-    this.exprAllowed = false
-  } else if (out === types.b_tmpl) {
-    this.exprAllowed = true
-  } else {
-    this.exprAllowed = !out.isExpr
-  }
-}
-
-tt.braceL.updateContext = function(prevType) {
-  this.context.push(this.braceIsBlock(prevType) ? types.b_stat : types.b_expr)
-  this.exprAllowed = true
-}
-
-tt.dollarBraceL.updateContext = function() {
-  this.context.push(types.b_tmpl)
-  this.exprAllowed = true
-}
-
-tt.parenL.updateContext = function(prevType) {
-  var statementParens = prevType === tt._if || prevType === tt._for || prevType === tt._with || prevType === tt._while
-  this.context.push(statementParens ? types.p_stat : types.p_expr)
-  this.exprAllowed = true
-}
-
-tt.incDec.updateContext = function() {
-  // tokExprAllowed stays unchanged
-}
-
-tt._function.updateContext = function(prevType) {
-  if (prevType.beforeExpr && prevType !== tt.semi && prevType !== tt._else &&
-      !((prevType === tt.colon || prevType === tt.braceL) && this.curContext() === types.b_stat))
-    this.context.push(types.f_expr)
-  this.exprAllowed = false
-}
-
-tt.backQuote.updateContext = function() {
-  if (this.curContext() === types.q_tmpl)
-    this.context.pop()
-  else
-    this.context.push(types.q_tmpl)
-  this.exprAllowed = false
-}
-
-tt.star.updateContext = function(prevType) {
-  if (prevType == tt._function) {
-    if (this.curContext() === types.f_expr)
-      this.context[this.context.length - 1] = types.f_expr_gen
-    else
-      this.context.push(types.f_gen)
-  }
-  this.exprAllowed = true
-}
-
-tt.name.updateContext = function(prevType) {
-  var allowed = false
-  if (this.options.ecmaVersion >= 6) {
-    if (this.value == "of" && !this.exprAllowed ||
-        this.value == "yield" && this.inGeneratorContext())
-      allowed = true
-  }
-  this.exprAllowed = allowed
-}
-
-// Object type used to represent tokens. Note that normally, tokens
-// simply exist as properties on the parser object. This is only
-// used for the onToken callback and the external tokenizer.
-
-var Token = function Token(p) {
-  this.type = p.type
-  this.value = p.value
-  this.start = p.start
-  this.end = p.end
-  if (p.options.locations)
-    this.loc = new SourceLocation(p, p.startLoc, p.endLoc)
-  if (p.options.ranges)
-    this.range = [p.start, p.end]
-};
-
-// ## Tokenizer
-
-var pp$8 = Parser.prototype
-
-// Are we running under Rhino?
-var isRhino = typeof Packages == "object" && Object.prototype.toString.call(Packages) == "[object JavaPackage]"
-
-// Move to the next token
-
-pp$8.next = function() {
-  if (this.options.onToken)
-    this.options.onToken(new Token(this))
-
-  this.lastTokEnd = this.end
-  this.lastTokStart = this.start
-  this.lastTokEndLoc = this.endLoc
-  this.lastTokStartLoc = this.startLoc
-  this.nextToken()
-}
-
-pp$8.getToken = function() {
-  this.next()
-  return new Token(this)
-}
-
-// If we're in an ES6 environment, make parsers iterable
-if (typeof Symbol !== "undefined")
-  pp$8[Symbol.iterator] = function() {
-    var this$1 = this;
-
-    return {
-      next: function () {
-        var token = this$1.getToken()
-        return {
-          done: token.type === tt.eof,
-          value: token
-        }
-      }
-    }
-  }
-
-// Toggle strict mode. Re-reads the next number or string to please
-// pedantic tests (`"use strict"; 010;` should fail).
-
-pp$8.curContext = function() {
-  return this.context[this.context.length - 1]
-}
-
-// Read a single token, updating the parser object's token-related
-// properties.
-
-pp$8.nextToken = function() {
-  var curContext = this.curContext()
-  if (!curContext || !curContext.preserveSpace) this.skipSpace()
-
-  this.start = this.pos
-  if (this.options.locations) this.startLoc = this.curPosition()
-  if (this.pos >= this.input.length) return this.finishToken(tt.eof)
-
-  if (curContext.override) return curContext.override(this)
-  else this.readToken(this.fullCharCodeAtPos())
-}
-
-pp$8.readToken = function(code) {
-  // Identifier or keyword. '\uXXXX' sequences are allowed in
-  // identifiers, so '\' also dispatches to that.
-  if (isIdentifierStart(code, this.options.ecmaVersion >= 6) || code === 92 /* '\' */)
-    return this.readWord()
-
-  return this.getTokenFromCode(code)
-}
-
-pp$8.fullCharCodeAtPos = function() {
-  var code = this.input.charCodeAt(this.pos)
-  if (code <= 0xd7ff || code >= 0xe000) return code
-  var next = this.input.charCodeAt(this.pos + 1)
-  return (code << 10) + next - 0x35fdc00
-}
-
-pp$8.skipBlockComment = function() {
-  var this$1 = this;
-
-  var startLoc = this.options.onComment && this.curPosition()
-  var start = this.pos, end = this.input.indexOf("*/", this.pos += 2)
-  if (end === -1) this.raise(this.pos - 2, "Unterminated comment")
-  this.pos = end + 2
-  if (this.options.locations) {
-    lineBreakG.lastIndex = start
-    var match
-    while ((match = lineBreakG.exec(this.input)) && match.index < this.pos) {
-      ++this$1.curLine
-      this$1.lineStart = match.index + match[0].length
-    }
-  }
-  if (this.options.onComment)
-    this.options.onComment(true, this.input.slice(start + 2, end), start, this.pos,
-                           startLoc, this.curPosition())
-}
-
-pp$8.skipLineComment = function(startSkip) {
-  var this$1 = this;
-
-  var start = this.pos
-  var startLoc = this.options.onComment && this.curPosition()
-  var ch = this.input.charCodeAt(this.pos += startSkip)
-  while (this.pos < this.input.length && ch !== 10 && ch !== 13 && ch !== 8232 && ch !== 8233) {
-    ++this$1.pos
-    ch = this$1.input.charCodeAt(this$1.pos)
-  }
-  if (this.options.onComment)
-    this.options.onComment(false, this.input.slice(start + startSkip, this.pos), start, this.pos,
-                           startLoc, this.curPosition())
-}
-
-// Called at the start of the parse and after every token. Skips
-// whitespace and comments, and.
-
-pp$8.skipSpace = function() {
-  var this$1 = this;
-
-  loop: while (this.pos < this.input.length) {
-    var ch = this$1.input.charCodeAt(this$1.pos)
-    switch (ch) {
-    case 32: case 160: // ' '
-      ++this$1.pos
-      break
-    case 13:
-      if (this$1.input.charCodeAt(this$1.pos + 1) === 10) {
-        ++this$1.pos
-      }
-    case 10: case 8232: case 8233:
-      ++this$1.pos
-      if (this$1.options.locations) {
-        ++this$1.curLine
-        this$1.lineStart = this$1.pos
-      }
-      break
-    case 47: // '/'
-      switch (this$1.input.charCodeAt(this$1.pos + 1)) {
-      case 42: // '*'
-        this$1.skipBlockComment()
-        break
-      case 47:
-        this$1.skipLineComment(2)
-        break
-      default:
-        break loop
-      }
-      break
-    default:
-      if (ch > 8 && ch < 14 || ch >= 5760 && nonASCIIwhitespace.test(String.fromCharCode(ch))) {
-        ++this$1.pos
-      } else {
-        break loop
-      }
-    }
-  }
-}
-
-// Called at the end of every token. Sets `end`, `val`, and
-// maintains `context` and `exprAllowed`, and skips the space after
-// the token, so that the next one's `start` will point at the
-// right position.
-
-pp$8.finishToken = function(type, val) {
-  this.end = this.pos
-  if (this.options.locations) this.endLoc = this.curPosition()
-  var prevType = this.type
-  this.type = type
-  this.value = val
-
-  this.updateContext(prevType)
-}
-
-// ### 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.
-//
-pp$8.readToken_dot = function() {
-  var next = this.input.charCodeAt(this.pos + 1)
-  if (next >= 48 && next <= 57) return this.readNumber(true)
-  var next2 = this.input.charCodeAt(this.pos + 2)
-  if (this.options.ecmaVersion >= 6 && next === 46 && next2 === 46) { // 46 = dot '.'
-    this.pos += 3
-    return this.finishToken(tt.ellipsis)
-  } else {
-    ++this.pos
-    return this.finishToken(tt.dot)
-  }
-}
-
-pp$8.readToken_slash = function() { // '/'
-  var next = this.input.charCodeAt(this.pos + 1)
-  if (this.exprAllowed) { ++this.pos; return this.readRegexp() }
-  if (next === 61) return this.finishOp(tt.assign, 2)
-  return this.finishOp(tt.slash, 1)
-}
-
-pp$8.readToken_mult_modulo_exp = function(code) { // '%*'
-  var next = this.input.charCodeAt(this.pos + 1)
-  var size = 1
-  var tokentype = code === 42 ? tt.star : tt.modulo
-
-  // exponentiation operator ** and **=
-  if (this.options.ecmaVersion >= 7 && next === 42) {
-    ++size
-    tokentype = tt.starstar
-    next = this.input.charCodeAt(this.pos + 2)
-  }
-
-  if (next === 61) return this.finishOp(tt.assign, size + 1)
-  return this.finishOp(tokentype, size)
-}
-
-pp$8.readToken_pipe_amp = function(code) { // '|&'
-  var next = this.input.charCodeAt(this.pos + 1)
-  if (next === code) return this.finishOp(code === 124 ? tt.logicalOR : tt.logicalAND, 2)
-  if (next === 61) return this.finishOp(tt.assign, 2)
-  return this.finishOp(code === 124 ? tt.bitwiseOR : tt.bitwiseAND, 1)
-}
-
-pp$8.readToken_caret = function() { // '^'
-  var next = this.input.charCodeAt(this.pos + 1)
-  if (next === 61) return this.finishOp(tt.assign, 2)
-  return this.finishOp(tt.bitwiseXOR, 1)
-}
-
-pp$8.readToken_plus_min = function(code) { // '+-'
-  var next = this.input.charCodeAt(this.pos + 1)
-  if (next === code) {
-    if (next == 45 && this.input.charCodeAt(this.pos + 2) == 62 &&
-        lineBreak.test(this.input.slice(this.lastTokEnd, this.pos))) {
-      // A `-->` line comment
-      this.skipLineComment(3)
-      this.skipSpace()
-      return this.nextToken()
-    }
-    return this.finishOp(tt.incDec, 2)
-  }
-  if (next === 61) return this.finishOp(tt.assign, 2)
-  return this.finishOp(tt.plusMin, 1)
-}
-
-pp$8.readToken_lt_gt = function(code) { // '<>'
-  var next = this.input.charCodeAt(this.pos + 1)
-  var size = 1
-  if (next === code) {
-    size = code === 62 && this.input.charCodeAt(this.pos + 2) === 62 ? 3 : 2
-    if (this.input.charCodeAt(this.pos + size) === 61) return this.finishOp(tt.assign, size + 1)
-    return this.finishOp(tt.bitShift, size)
-  }
-  if (next == 33 && code == 60 && this.input.charCodeAt(this.pos + 2) == 45 &&
-      this.input.charCodeAt(this.pos + 3) == 45) {
-    if (this.inModule) this.unexpected()
-    // `<!--`, an XML-style comment that should be interpreted as a line comment
-    this.skipLineComment(4)
-    this.skipSpace()
-    return this.nextToken()
-  }
-  if (next === 61) size = 2
-  return this.finishOp(tt.relational, size)
-}
-
-pp$8.readToken_eq_excl = function(code) { // '=!'
-  var next = this.input.charCodeAt(this.pos + 1)
-  if (next === 61) return this.finishOp(tt.equality, this.input.charCodeAt(this.pos + 2) === 61 ? 3 : 2)
-  if (code === 61 && next === 62 && this.options.ecmaVersion >= 6) { // '=>'
-    this.pos += 2
-    return this.finishToken(tt.arrow)
-  }
-  return this.finishOp(code === 61 ? tt.eq : tt.prefix, 1)
-}
-
-pp$8.getTokenFromCode = function(code) {
-  switch (code) {
-    // The interpretation of a dot depends on whether it is followed
-    // by a digit or another two dots.
-  case 46: // '.'
-    return this.readToken_dot()
-
-    // Punctuation tokens.
-  case 40: ++this.pos; return this.finishToken(tt.parenL)
-  case 41: ++this.pos; return this.finishToken(tt.parenR)
-  case 59: ++this.pos; return this.finishToken(tt.semi)
-  case 44: ++this.pos; return this.finishToken(tt.comma)
-  case 91: ++this.pos; return this.finishToken(tt.bracketL)
-  case 93: ++this.pos; return this.finishToken(tt.bracketR)
-  case 123: ++this.pos; return this.finishToken(tt.braceL)
-  case 125: ++this.pos; return this.finishToken(tt.braceR)
-  case 58: ++this.pos; return this.finishToken(tt.colon)
-  case 63: ++this.pos; return this.finishToken(tt.question)
-
-  case 96: // '`'
-    if (this.options.ecmaVersion < 6) break
-    ++this.pos
-    return this.finishToken(tt.backQuote)
-
-  case 48: // '0'
-    var next = this.input.charCodeAt(this.pos + 1)
-    if (next === 120 || next === 88) return this.readRadixNumber(16) // '0x', '0X' - hex number
-    if (this.options.ecmaVersion >= 6) {
-      if (next === 111 || next === 79) return this.readRadixNumber(8) // '0o', '0O' - octal number
-      if (next === 98 || next === 66) return this.readRadixNumber(2) // '0b', '0B' - binary number
-    }
-    // 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 this.readNumber(false)
-
-    // Quotes produce strings.
-  case 34: case 39: // '"', "'"
-    return this.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 this.readToken_slash()
-
-  case 37: case 42: // '%*'
-    return this.readToken_mult_modulo_exp(code)
-
-  case 124: case 38: // '|&'
-    return this.readToken_pipe_amp(code)
-
-  case 94: // '^'
-    return this.readToken_caret()
-
-  case 43: case 45: // '+-'
-    return this.readToken_plus_min(code)
-
-  case 60: case 62: // '<>'
-    return this.readToken_lt_gt(code)
-
-  case 61: case 33: // '=!'
-    return this.readToken_eq_excl(code)
-
-  case 126: // '~'
-    return this.finishOp(tt.prefix, 1)
-  }
-
-  this.raise(this.pos, "Unexpected character '" + codePointToString(code) + "'")
-}
-
-pp$8.finishOp = function(type, size) {
-  var str = this.input.slice(this.pos, this.pos + size)
-  this.pos += size
-  return this.finishToken(type, str)
-}
-
-// Parse a regular expression. Some context-awareness is necessary,
-// since a '/' inside a '[]' set does not end the expression.
-
-function tryCreateRegexp(src, flags, throwErrorAt, parser) {
-  try {
-    return new RegExp(src, flags)
-  } catch (e) {
-    if (throwErrorAt !== undefined) {
-      if (e instanceof SyntaxError) parser.raise(throwErrorAt, "Error parsing regular expression: " + e.message)
-      throw e
-    }
-  }
-}
-
-var regexpUnicodeSupport = !!tryCreateRegexp("\uffff", "u")
-
-pp$8.readRegexp = function() {
-  var this$1 = this;
-
-  var escaped, inClass, start = this.pos
-  for (;;) {
-    if (this$1.pos >= this$1.input.length) this$1.raise(start, "Unterminated regular expression")
-    var ch = this$1.input.charAt(this$1.pos)
-    if (lineBreak.test(ch)) this$1.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
-    ++this$1.pos
-  }
-  var content = this.input.slice(start, this.pos)
-  ++this.pos
-  // Need to use `readWord1` because '\uXXXX' sequences are allowed
-  // here (don't ask).
-  var mods = this.readWord1()
-  var tmp = content, tmpFlags = ""
-  if (mods) {
-    var validFlags = /^[gim]*$/
-    if (this.options.ecmaVersion >= 6) validFlags = /^[gimuy]*$/
-    if (!validFlags.test(mods)) this.raise(start, "Invalid regular expression flag")
-    if (mods.indexOf("u") >= 0) {
-      if (regexpUnicodeSupport) {
-        tmpFlags = "u"
-      } else {
-        // Replace each astral symbol and every Unicode escape sequence that
-        // possibly represents an astral symbol or a paired surrogate with a
-        // single ASCII symbol to avoid throwing on regular expressions that
-        // are only valid in combination with the `/u` flag.
-        // Note: replacing with the ASCII symbol `x` might cause false
-        // negatives in unlikely scenarios. For example, `[\u{61}-b]` is a
-        // perfectly valid pattern that is equivalent to `[a-b]`, but it would
-        // be replaced by `[x-b]` which throws an error.
-        tmp = tmp.replace(/\\u\{([0-9a-fA-F]+)\}/g, function (_match, code, offset) {
-          code = Number("0x" + code)
-          if (code > 0x10FFFF) this$1.raise(start + offset + 3, "Code point out of bounds")
-          return "x"
-        })
-        tmp = tmp.replace(/\\u([a-fA-F0-9]{4})|[\uD800-\uDBFF][\uDC00-\uDFFF]/g, "x")
-        tmpFlags = tmpFlags.replace("u", "")
-      }
-    }
-  }
-  // Detect invalid regular expressions.
-  var value = null
-  // Rhino's regular expression parser is flaky and throws uncatchable exceptions,
-  // so don't do detection if we are running under Rhino
-  if (!isRhino) {
-    tryCreateRegexp(tmp, tmpFlags, start, this)
-    // Get a regular expression object for this pattern-flag pair, or `null` in
-    // case the current environment doesn't support the flags it uses.
-    value = tryCreateRegexp(content, mods)
-  }
-  return this.finishToken(tt.regexp, {pattern: content, flags: mods, value: 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.
-
-pp$8.readInt = function(radix, len) {
-  var this$1 = this;
-
-  var start = this.pos, total = 0
-  for (var i = 0, e = len == null ? Infinity : len; i < e; ++i) {
-    var code = this$1.input.charCodeAt(this$1.pos), 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
-    ++this$1.pos
-    total = total * radix + val
-  }
-  if (this.pos === start || len != null && this.pos - start !== len) return null
-
-  return total
-}
-
-pp$8.readRadixNumber = function(radix) {
-  this.pos += 2 // 0x
-  var val = this.readInt(radix)
-  if (val == null) this.raise(this.start + 2, "Expected number in radix " + radix)
-  if (isIdentifierStart(this.fullCharCodeAtPos())) this.raise(this.pos, "Identifier directly after number")
-  return this.finishToken(tt.num, val)
-}
-
-// Read an integer, octal integer, or floating-point number.
-
-pp$8.readNumber = function(startsWithDot) {
-  var start = this.pos, isFloat = false, octal = this.input.charCodeAt(this.pos) === 48
-  if (!startsWithDot && this.readInt(10) === null) this.raise(start, "Invalid number")
-  if (octal && this.pos == start + 1) octal = false
-  var next = this.input.charCodeAt(this.pos)
-  if (next === 46 && !octal) { // '.'
-    ++this.pos
-    this.readInt(10)
-    isFloat = true
-    next = this.input.charCodeAt(this.pos)
-  }
-  if ((next === 69 || next === 101) && !octal) { // 'eE'
-    next = this.input.charCodeAt(++this.pos)
-    if (next === 43 || next === 45) ++this.pos // '+-'
-    if (this.readInt(10) === null) this.raise(start, "Invalid number")
-    isFloat = true
-  }
-  if (isIdentifierStart(this.fullCharCodeAtPos())) this.raise(this.pos, "Identifier directly after number")
-
-  var str = this.input.slice(start, this.pos), val
-  if (isFloat) val = parseFloat(str)
-  else if (!octal || str.length === 1) val = parseInt(str, 10)
-  else if (/[89]/.test(str) || this.strict) this.raise(start, "Invalid number")
-  else val = parseInt(str, 8)
-  return this.finishToken(tt.num, val)
-}
-
-// Read a string value, interpreting backslash-escapes.
-
-pp$8.readCodePoint = function() {
-  var ch = this.input.charCodeAt(this.pos), code
-
-  if (ch === 123) {
-    if (this.options.ecmaVersion < 6) this.unexpected()
-    var codePos = ++this.pos
-    code = this.readHexChar(this.input.indexOf("}", this.pos) - this.pos)
-    ++this.pos
-    if (code > 0x10FFFF) this.raise(codePos, "Code point out of bounds")
-  } else {
-    code = this.readHexChar(4)
-  }
-  return code
-}
-
-function codePointToString(code) {
-  // UTF-16 Decoding
-  if (code <= 0xFFFF) return String.fromCharCode(code)
-  code -= 0x10000
-  return String.fromCharCode((code >> 10) + 0xD800, (code & 1023) + 0xDC00)
-}
-
-pp$8.readString = function(quote) {
-  var this$1 = this;
-
-  var out = "", chunkStart = ++this.pos
-  for (;;) {
-    if (this$1.pos >= this$1.input.length) this$1.raise(this$1.start, "Unterminated string constant")
-    var ch = this$1.input.charCodeAt(this$1.pos)
-    if (ch === quote) break
-    if (ch === 92) { // '\'
-      out += this$1.input.slice(chunkStart, this$1.pos)
-      out += this$1.readEscapedChar(false)
-      chunkStart = this$1.pos
-    } else {
-      if (isNewLine(ch)) this$1.raise(this$1.start, "Unterminated string constant")
-      ++this$1.pos
-    }
-  }
-  out += this.input.slice(chunkStart, this.pos++)
-  return this.finishToken(tt.string, out)
-}
-
-// Reads template string tokens.
-
-pp$8.readTmplToken = function() {
-  var this$1 = this;
-
-  var out = "", chunkStart = this.pos
-  for (;;) {
-    if (this$1.pos >= this$1.input.length) this$1.raise(this$1.start, "Unterminated template")
-    var ch = this$1.input.charCodeAt(this$1.pos)
-    if (ch === 96 || ch === 36 && this$1.input.charCodeAt(this$1.pos + 1) === 123) { // '`', '${'
-      if (this$1.pos === this$1.start && this$1.type === tt.template) {
-        if (ch === 36) {
-          this$1.pos += 2
-          return this$1.finishToken(tt.dollarBraceL)
-        } else {
-          ++this$1.pos
-          return this$1.finishToken(tt.backQuote)
-        }
-      }
-      out += this$1.input.slice(chunkStart, this$1.pos)
-      return this$1.finishToken(tt.template, out)
-    }
-    if (ch === 92) { // '\'
-      out += this$1.input.slice(chunkStart, this$1.pos)
-      out += this$1.readEscapedChar(true)
-      chunkStart = this$1.pos
-    } else if (isNewLine(ch)) {
-      out += this$1.input.slice(chunkStart, this$1.pos)
-      ++this$1.pos
-      switch (ch) {
-      case 13:
-        if (this$1.input.charCodeAt(this$1.pos) === 10) ++this$1.pos
-      case 10:
-        out += "\n"
-        break
-      default:
-        out += String.fromCharCode(ch)
-        break
-      }
-      if (this$1.options.locations) {
-        ++this$1.curLine
-        this$1.lineStart = this$1.pos
-      }
-      chunkStart = this$1.pos
-    } else {
-      ++this$1.pos
-    }
-  }
-}
-
-// Used to read escaped characters
-
-pp$8.readEscapedChar = function(inTemplate) {
-  var ch = this.input.charCodeAt(++this.pos)
-  ++this.pos
-  switch (ch) {
-  case 110: return "\n" // 'n' -> '\n'
-  case 114: return "\r" // 'r' -> '\r'
-  case 120: return String.fromCharCode(this.readHexChar(2)) // 'x'
-  case 117: return codePointToString(this.readCodePoint()) // 'u'
-  case 116: return "\t" // 't' -> '\t'
-  case 98: return "\b" // 'b' -> '\b'
-  case 118: return "\u000b" // 'v' -> '\u000b'
-  case 102: return "\f" // 'f' -> '\f'
-  case 13: if (this.input.charCodeAt(this.pos) === 10) ++this.pos // '\r\n'
-  case 10: // ' \n'
-    if (this.options.locations) { this.lineStart = this.pos; ++this.curLine }
-    return ""
-  default:
-    if (ch >= 48 && ch <= 55) {
-      var octalStr = this.input.substr(this.pos - 1, 3).match(/^[0-7]+/)[0]
-      var octal = parseInt(octalStr, 8)
-      if (octal > 255) {
-        octalStr = octalStr.slice(0, -1)
-        octal = parseInt(octalStr, 8)
-      }
-      if (octalStr !== "0" && (this.strict || inTemplate)) {
-        this.raise(this.pos - 2, "Octal literal in strict mode")
-      }
-      this.pos += octalStr.length - 1
-      return String.fromCharCode(octal)
-    }
-    return String.fromCharCode(ch)
-  }
-}
-
-// Used to read character escape sequences ('\x', '\u', '\U').
-
-pp$8.readHexChar = function(len) {
-  var codePos = this.pos
-  var n = this.readInt(16, len)
-  if (n === null) this.raise(codePos, "Bad character escape sequence")
-  return n
-}
-
-// Read an identifier, and return it as a string. Sets `this.containsEsc`
-// to whether the word contained a '\u' escape.
-//
-// Incrementally adds only escaped chars, adding other chunks as-is
-// as a micro-optimization.
-
-pp$8.readWord1 = function() {
-  var this$1 = this;
-
-  this.containsEsc = false
-  var word = "", first = true, chunkStart = this.pos
-  var astral = this.options.ecmaVersion >= 6
-  while (this.pos < this.input.length) {
-    var ch = this$1.fullCharCodeAtPos()
-    if (isIdentifierChar(ch, astral)) {
-      this$1.pos += ch <= 0xffff ? 1 : 2
-    } else if (ch === 92) { // "\"
-      this$1.containsEsc = true
-      word += this$1.input.slice(chunkStart, this$1.pos)
-      var escStart = this$1.pos
-      if (this$1.input.charCodeAt(++this$1.pos) != 117) // "u"
-        this$1.raise(this$1.pos, "Expecting Unicode escape sequence \\uXXXX")
-      ++this$1.pos
-      var esc = this$1.readCodePoint()
-      if (!(first ? isIdentifierStart : isIdentifierChar)(esc, astral))
-        this$1.raise(escStart, "Invalid Unicode escape")
-      word += codePointToString(esc)
-      chunkStart = this$1.pos
-    } else {
-      break
-    }
-    first = false
-  }
-  return word + this.input.slice(chunkStart, this.pos)
-}
-
-// Read an identifier or keyword token. Will check for reserved
-// words when necessary.
-
-pp$8.readWord = function() {
-  var word = this.readWord1()
-  var type = tt.name
-  if (this.keywords.test(word)) {
-    if (this.containsEsc) this.raiseRecoverable(this.start, "Escape sequence in keyword " + word)
-    type = keywordTypes[word]
-  }
-  return this.finishToken(type, word)
-}
-
-// Acorn is a tiny, fast JavaScript parser written in JavaScript.
-//
-// Acorn was written by Marijn Haverbeke, Ingvar Stepanyan, and
-// various contributors and released under an MIT license.
-//
-// Git repositories for Acorn are available at
-//
-//     http://marijnhaverbeke.nl/git/acorn
-//     https://github.com/ternjs/acorn.git
-//
-// Please use the [github bug tracker][ghbt] to report issues.
-//
-// [ghbt]: https://github.com/ternjs/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
-
-var version = "5.0.3"
-
-// 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].
-//
-// [api]: https://developer.mozilla.org/en-US/docs/SpiderMonkey/Parser_API
-
-function parse(input, options) {
-  return new Parser(options, input).parse()
-}
-
-// This function tries to parse a single expression at a given
-// offset in a string. Useful for parsing mixed-language formats
-// that embed JavaScript expressions.
-
-function parseExpressionAt(input, pos, options) {
-  var p = new Parser(options, input, pos)
-  p.nextToken()
-  return p.parseExpression()
-}
-
-// Acorn is organized as a tokenizer and a recursive-descent parser.
-// The `tokenizer` export provides an interface to the tokenizer.
-
-function tokenizer(input, options) {
-  return new Parser(options, input)
-}
-
-// This is a terrible kludge to support the existing, pre-ES6
-// interface where the loose parser module retroactively adds exports
-// to this module.
-// eslint-disable-line camelcase
-function addLooseExports(parse, Parser, plugins) {
-  exports.parse_dammit = parse // eslint-disable-line camelcase
-  exports.LooseParser = Parser
-  exports.pluginsLoose = plugins
-}
-
-exports.version = version;
-exports.parse = parse;
-exports.parseExpressionAt = parseExpressionAt;
-exports.tokenizer = tokenizer;
-exports.addLooseExports = addLooseExports;
-exports.Parser = Parser;
-exports.plugins = plugins;
-exports.defaultOptions = defaultOptions;
-exports.Position = Position;
-exports.SourceLocation = SourceLocation;
-exports.getLineInfo = getLineInfo;
-exports.Node = Node;
-exports.TokenType = TokenType;
-exports.tokTypes = tt;
-exports.keywordTypes = keywordTypes;
-exports.TokContext = TokContext;
-exports.tokContexts = types;
-exports.isIdentifierChar = isIdentifierChar;
-exports.isIdentifierStart = isIdentifierStart;
-exports.Token = Token;
-exports.isNewLine = isNewLine;
-exports.lineBreak = lineBreak;
-exports.lineBreakG = lineBreakG;
-exports.nonASCIIwhitespace = nonASCIIwhitespace;
-
-Object.defineProperty(exports, '__esModule', { value: true });
-
-})));
\ No newline at end of file