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diff --git a/node_modules/@babel/plugin-transform-block-scoping/README.md b/node_modules/@babel/plugin-transform-block-scoping/README.md
new file mode 100644
index 00000000..7c174e50
--- /dev/null
+++ b/node_modules/@babel/plugin-transform-block-scoping/README.md
@@ -0,0 +1,103 @@
+# @babel/plugin-transform-block-scoping
+
+> Compile ES2015 block scoping (const and let) to ES5
+
+## Examples
+
+**In**
+
+```javascript
+{
+  let a = 3
+}
+
+let a = 3
+```
+
+**Out**
+
+```javascript
+{
+  var _a = 3;
+}
+
+var a = 3;
+```
+
+## Constant checks
+
+This plugin also validates all `const` variables.
+Reassignment of constants is a runtime error and it will insert the necessary error code for those.
+
+## Installation
+
+```sh
+npm install --save-dev @babel/plugin-transform-block-scoping
+```
+
+## Usage
+
+### Via `.babelrc` (Recommended)
+
+**.babelrc**
+
+Without options:
+
+```json
+{
+  "plugins": ["@babel/plugin-transform-block-scoping"]
+}
+```
+
+With options:
+
+```json
+{
+  "plugins": [
+    ["@babel/plugin-transform-block-scoping", {
+      "throwIfClosureRequired": true
+    }]
+  ]
+}
+```
+
+### Via CLI
+
+```sh
+babel --plugins @babel/plugin-transform-block-scoping script.js
+```
+
+### Via Node API
+
+```javascript
+require("@babel/core").transform("code", {
+  plugins: ["@babel/plugin-transform-block-scoping"]
+});
+```
+
+## Options
+
+### `throwIfClosureRequired`
+`boolean`, defaults to `false`.
+
+In cases such as the following it's impossible to rewrite let/const without adding an additional function and closure while transforming:
+
+```javascript
+for (let i = 0; i < 5; i++) {
+  setTimeout(() => console.log(i), 1);
+}
+```
+
+In extremely performance-sensitive code, this can be undesirable. If `"throwIfClosureRequired": true` is set, Babel throws when transforming these patterns instead of automatically adding an additional function.
+
+### `tdz`
+`boolean`, defaults to `false`.
+
+By default this plugin will ignore the *temporal dead zone (TDZ)* for block-scoped variables. The following code will **not throw an error when transpiled with Babel, which is not spec compliant**:
+
+```javascript
+i
+let i;
+```
+
+If you need these errors you can tell Babel to try and find them by setting `"tdz": true` for this plugin. However, the current implementation might not get all edge cases right and its best to just avoid code like this in the first place.
diff --git a/node_modules/@babel/plugin-transform-block-scoping/lib/index.js b/node_modules/@babel/plugin-transform-block-scoping/lib/index.js
new file mode 100644
index 00000000..e70fe5a0
--- /dev/null
+++ b/node_modules/@babel/plugin-transform-block-scoping/lib/index.js
@@ -0,0 +1,747 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.default = void 0;
+
+function _helperPluginUtils() {
+  const data = require("@babel/helper-plugin-utils");
+
+  _helperPluginUtils = function _helperPluginUtils() {
+    return data;
+  };
+
+  return data;
+}
+
+var _tdz = require("./tdz");
+
+function _values() {
+  const data = _interopRequireDefault(require("lodash/values"));
+
+  _values = function _values() {
+    return data;
+  };
+
+  return data;
+}
+
+function _extend() {
+  const data = _interopRequireDefault(require("lodash/extend"));
+
+  _extend = function _extend() {
+    return data;
+  };
+
+  return data;
+}
+
+function _core() {
+  const data = require("@babel/core");
+
+  _core = function _core() {
+    return data;
+  };
+
+  return data;
+}
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+const DONE = new WeakSet();
+
+var _default = (0, _helperPluginUtils().declare)((api, opts) => {
+  api.assertVersion(7);
+  const _opts$throwIfClosureR = opts.throwIfClosureRequired,
+        throwIfClosureRequired = _opts$throwIfClosureR === void 0 ? false : _opts$throwIfClosureR,
+        _opts$tdz = opts.tdz,
+        tdzEnabled = _opts$tdz === void 0 ? false : _opts$tdz;
+
+  if (typeof throwIfClosureRequired !== "boolean") {
+    throw new Error(`.throwIfClosureRequired must be a boolean, or undefined`);
+  }
+
+  if (typeof tdzEnabled !== "boolean") {
+    throw new Error(`.throwIfClosureRequired must be a boolean, or undefined`);
+  }
+
+  return {
+    visitor: {
+      VariableDeclaration(path) {
+        const node = path.node,
+              parent = path.parent,
+              scope = path.scope;
+        if (!isBlockScoped(node)) return;
+        convertBlockScopedToVar(path, null, parent, scope, true);
+
+        if (node._tdzThis) {
+          const nodes = [node];
+
+          for (let i = 0; i < node.declarations.length; i++) {
+            const decl = node.declarations[i];
+
+            if (decl.init) {
+              const assign = _core().types.assignmentExpression("=", decl.id, decl.init);
+
+              assign._ignoreBlockScopingTDZ = true;
+              nodes.push(_core().types.expressionStatement(assign));
+            }
+
+            decl.init = this.addHelper("temporalUndefined");
+          }
+
+          node._blockHoist = 2;
+
+          if (path.isCompletionRecord()) {
+            nodes.push(_core().types.expressionStatement(scope.buildUndefinedNode()));
+          }
+
+          path.replaceWithMultiple(nodes);
+        }
+      },
+
+      Loop(path, state) {
+        const parent = path.parent,
+              scope = path.scope;
+        path.ensureBlock();
+        const blockScoping = new BlockScoping(path, path.get("body"), parent, scope, throwIfClosureRequired, tdzEnabled, state);
+        const replace = blockScoping.run();
+        if (replace) path.replaceWith(replace);
+      },
+
+      CatchClause(path, state) {
+        const parent = path.parent,
+              scope = path.scope;
+        const blockScoping = new BlockScoping(null, path.get("body"), parent, scope, throwIfClosureRequired, tdzEnabled, state);
+        blockScoping.run();
+      },
+
+      "BlockStatement|SwitchStatement|Program"(path, state) {
+        if (!ignoreBlock(path)) {
+          const blockScoping = new BlockScoping(null, path, path.parent, path.scope, throwIfClosureRequired, tdzEnabled, state);
+          blockScoping.run();
+        }
+      }
+
+    }
+  };
+});
+
+exports.default = _default;
+
+function ignoreBlock(path) {
+  return _core().types.isLoop(path.parent) || _core().types.isCatchClause(path.parent);
+}
+
+const buildRetCheck = (0, _core().template)(`
+  if (typeof RETURN === "object") return RETURN.v;
+`);
+
+function isBlockScoped(node) {
+  if (!_core().types.isVariableDeclaration(node)) return false;
+  if (node[_core().types.BLOCK_SCOPED_SYMBOL]) return true;
+  if (node.kind !== "let" && node.kind !== "const") return false;
+  return true;
+}
+
+function isInLoop(path) {
+  const loopOrFunctionParent = path.find(path => path.isLoop() || path.isFunction());
+  return loopOrFunctionParent && loopOrFunctionParent.isLoop();
+}
+
+function convertBlockScopedToVar(path, node, parent, scope, moveBindingsToParent = false) {
+  if (!node) {
+    node = path.node;
+  }
+
+  if (isInLoop(path) && !_core().types.isFor(parent)) {
+    for (let i = 0; i < node.declarations.length; i++) {
+      const declar = node.declarations[i];
+      declar.init = declar.init || scope.buildUndefinedNode();
+    }
+  }
+
+  node[_core().types.BLOCK_SCOPED_SYMBOL] = true;
+  node.kind = "var";
+
+  if (moveBindingsToParent) {
+    const parentScope = scope.getFunctionParent() || scope.getProgramParent();
+    const ids = path.getBindingIdentifiers();
+
+    for (const name in ids) {
+      const binding = scope.getOwnBinding(name);
+      if (binding) binding.kind = "var";
+      scope.moveBindingTo(name, parentScope);
+    }
+  }
+}
+
+function isVar(node) {
+  return _core().types.isVariableDeclaration(node, {
+    kind: "var"
+  }) && !isBlockScoped(node);
+}
+
+const letReferenceBlockVisitor = _core().traverse.visitors.merge([{
+  Loop: {
+    enter(path, state) {
+      state.loopDepth++;
+    },
+
+    exit(path, state) {
+      state.loopDepth--;
+    }
+
+  },
+
+  Function(path, state) {
+    if (state.loopDepth > 0) {
+      path.traverse(letReferenceFunctionVisitor, state);
+    }
+
+    return path.skip();
+  }
+
+}, _tdz.visitor]);
+
+const letReferenceFunctionVisitor = _core().traverse.visitors.merge([{
+  ReferencedIdentifier(path, state) {
+    const ref = state.letReferences[path.node.name];
+    if (!ref) return;
+    const localBinding = path.scope.getBindingIdentifier(path.node.name);
+    if (localBinding && localBinding !== ref) return;
+    state.closurify = true;
+  }
+
+}, _tdz.visitor]);
+
+const hoistVarDeclarationsVisitor = {
+  enter(path, self) {
+    const node = path.node,
+          parent = path.parent;
+
+    if (path.isForStatement()) {
+      if (isVar(node.init, node)) {
+        const nodes = self.pushDeclar(node.init);
+
+        if (nodes.length === 1) {
+          node.init = nodes[0];
+        } else {
+          node.init = _core().types.sequenceExpression(nodes);
+        }
+      }
+    } else if (path.isFor()) {
+      if (isVar(node.left, node)) {
+        self.pushDeclar(node.left);
+        node.left = node.left.declarations[0].id;
+      }
+    } else if (isVar(node, parent)) {
+      path.replaceWithMultiple(self.pushDeclar(node).map(expr => _core().types.expressionStatement(expr)));
+    } else if (path.isFunction()) {
+      return path.skip();
+    }
+  }
+
+};
+const loopLabelVisitor = {
+  LabeledStatement({
+    node
+  }, state) {
+    state.innerLabels.push(node.label.name);
+  }
+
+};
+const continuationVisitor = {
+  enter(path, state) {
+    if (path.isAssignmentExpression() || path.isUpdateExpression()) {
+      const bindings = path.getBindingIdentifiers();
+
+      for (const name in bindings) {
+        if (state.outsideReferences[name] !== path.scope.getBindingIdentifier(name)) {
+          continue;
+        }
+
+        state.reassignments[name] = true;
+      }
+    } else if (path.isReturnStatement()) {
+      state.returnStatements.push(path);
+    }
+  }
+
+};
+
+function loopNodeTo(node) {
+  if (_core().types.isBreakStatement(node)) {
+    return "break";
+  } else if (_core().types.isContinueStatement(node)) {
+    return "continue";
+  }
+}
+
+const loopVisitor = {
+  Loop(path, state) {
+    const oldIgnoreLabeless = state.ignoreLabeless;
+    state.ignoreLabeless = true;
+    path.traverse(loopVisitor, state);
+    state.ignoreLabeless = oldIgnoreLabeless;
+    path.skip();
+  },
+
+  Function(path) {
+    path.skip();
+  },
+
+  SwitchCase(path, state) {
+    const oldInSwitchCase = state.inSwitchCase;
+    state.inSwitchCase = true;
+    path.traverse(loopVisitor, state);
+    state.inSwitchCase = oldInSwitchCase;
+    path.skip();
+  },
+
+  "BreakStatement|ContinueStatement|ReturnStatement"(path, state) {
+    const node = path.node,
+          parent = path.parent,
+          scope = path.scope;
+    if (node[this.LOOP_IGNORE]) return;
+    let replace;
+    let loopText = loopNodeTo(node);
+
+    if (loopText) {
+      if (node.label) {
+        if (state.innerLabels.indexOf(node.label.name) >= 0) {
+          return;
+        }
+
+        loopText = `${loopText}|${node.label.name}`;
+      } else {
+        if (state.ignoreLabeless) return;
+        if (_core().types.isBreakStatement(node) && _core().types.isSwitchCase(parent)) return;
+      }
+
+      state.hasBreakContinue = true;
+      state.map[loopText] = node;
+      replace = _core().types.stringLiteral(loopText);
+    }
+
+    if (path.isReturnStatement()) {
+      state.hasReturn = true;
+      replace = _core().types.objectExpression([_core().types.objectProperty(_core().types.identifier("v"), node.argument || scope.buildUndefinedNode())]);
+    }
+
+    if (replace) {
+      replace = _core().types.returnStatement(replace);
+      replace[this.LOOP_IGNORE] = true;
+      path.skip();
+      path.replaceWith(_core().types.inherits(replace, node));
+    }
+  }
+
+};
+
+class BlockScoping {
+  constructor(loopPath, blockPath, parent, scope, throwIfClosureRequired, tdzEnabled, state) {
+    this.parent = parent;
+    this.scope = scope;
+    this.state = state;
+    this.throwIfClosureRequired = throwIfClosureRequired;
+    this.tdzEnabled = tdzEnabled;
+    this.blockPath = blockPath;
+    this.block = blockPath.node;
+    this.outsideLetReferences = Object.create(null);
+    this.hasLetReferences = false;
+    this.letReferences = Object.create(null);
+    this.body = [];
+
+    if (loopPath) {
+      this.loopParent = loopPath.parent;
+      this.loopLabel = _core().types.isLabeledStatement(this.loopParent) && this.loopParent.label;
+      this.loopPath = loopPath;
+      this.loop = loopPath.node;
+    }
+  }
+
+  run() {
+    const block = this.block;
+    if (DONE.has(block)) return;
+    DONE.add(block);
+    const needsClosure = this.getLetReferences();
+    this.checkConstants();
+
+    if (_core().types.isFunction(this.parent) || _core().types.isProgram(this.block)) {
+      this.updateScopeInfo();
+      return;
+    }
+
+    if (!this.hasLetReferences) return;
+
+    if (needsClosure) {
+      this.wrapClosure();
+    } else {
+      this.remap();
+    }
+
+    this.updateScopeInfo(needsClosure);
+
+    if (this.loopLabel && !_core().types.isLabeledStatement(this.loopParent)) {
+      return _core().types.labeledStatement(this.loopLabel, this.loop);
+    }
+  }
+
+  checkConstants() {
+    const scope = this.scope;
+    const state = this.state;
+
+    for (const name in scope.bindings) {
+      const binding = scope.bindings[name];
+      if (binding.kind !== "const") continue;
+      var _arr = binding.constantViolations;
+
+      for (var _i = 0; _i < _arr.length; _i++) {
+        const violation = _arr[_i];
+        const readOnlyError = state.addHelper("readOnlyError");
+
+        const throwNode = _core().types.callExpression(readOnlyError, [_core().types.stringLiteral(name)]);
+
+        if (violation.isAssignmentExpression()) {
+          violation.get("right").replaceWith(_core().types.sequenceExpression([throwNode, violation.get("right").node]));
+        } else if (violation.isUpdateExpression()) {
+          violation.replaceWith(_core().types.sequenceExpression([throwNode, violation.node]));
+        } else if (violation.isForXStatement()) {
+          violation.ensureBlock();
+          violation.node.body.body.unshift(_core().types.expressionStatement(throwNode));
+        }
+      }
+    }
+  }
+
+  updateScopeInfo(wrappedInClosure) {
+    const scope = this.scope;
+    const parentScope = scope.getFunctionParent() || scope.getProgramParent();
+    const letRefs = this.letReferences;
+
+    for (const key in letRefs) {
+      const ref = letRefs[key];
+      const binding = scope.getBinding(ref.name);
+      if (!binding) continue;
+
+      if (binding.kind === "let" || binding.kind === "const") {
+        binding.kind = "var";
+
+        if (wrappedInClosure) {
+          scope.removeBinding(ref.name);
+        } else {
+          scope.moveBindingTo(ref.name, parentScope);
+        }
+      }
+    }
+  }
+
+  remap() {
+    const letRefs = this.letReferences;
+    const scope = this.scope;
+
+    for (const key in letRefs) {
+      const ref = letRefs[key];
+
+      if (scope.parentHasBinding(key) || scope.hasGlobal(key)) {
+        if (scope.hasOwnBinding(key)) {
+          scope.rename(ref.name);
+        }
+
+        if (this.blockPath.scope.hasOwnBinding(key)) {
+          this.blockPath.scope.rename(ref.name);
+        }
+      }
+    }
+  }
+
+  wrapClosure() {
+    if (this.throwIfClosureRequired) {
+      throw this.blockPath.buildCodeFrameError("Compiling let/const in this block would add a closure " + "(throwIfClosureRequired).");
+    }
+
+    const block = this.block;
+    const outsideRefs = this.outsideLetReferences;
+
+    if (this.loop) {
+      for (const name in outsideRefs) {
+        const id = outsideRefs[name];
+
+        if (this.scope.hasGlobal(id.name) || this.scope.parentHasBinding(id.name)) {
+          delete outsideRefs[id.name];
+          delete this.letReferences[id.name];
+          this.scope.rename(id.name);
+          this.letReferences[id.name] = id;
+          outsideRefs[id.name] = id;
+        }
+      }
+    }
+
+    this.has = this.checkLoop();
+    this.hoistVarDeclarations();
+    const args = (0, _values().default)(outsideRefs).map(id => _core().types.cloneNode(id));
+    const params = args.map(id => _core().types.cloneNode(id));
+    const isSwitch = this.blockPath.isSwitchStatement();
+
+    const fn = _core().types.functionExpression(null, params, _core().types.blockStatement(isSwitch ? [block] : block.body));
+
+    this.addContinuations(fn);
+
+    let call = _core().types.callExpression(_core().types.nullLiteral(), args);
+
+    let basePath = ".callee";
+
+    const hasYield = _core().traverse.hasType(fn.body, "YieldExpression", _core().types.FUNCTION_TYPES);
+
+    if (hasYield) {
+      fn.generator = true;
+      call = _core().types.yieldExpression(call, true);
+      basePath = ".argument" + basePath;
+    }
+
+    const hasAsync = _core().traverse.hasType(fn.body, "AwaitExpression", _core().types.FUNCTION_TYPES);
+
+    if (hasAsync) {
+      fn.async = true;
+      call = _core().types.awaitExpression(call);
+      basePath = ".argument" + basePath;
+    }
+
+    let placeholderPath;
+    let index;
+
+    if (this.has.hasReturn || this.has.hasBreakContinue) {
+      const ret = this.scope.generateUid("ret");
+      this.body.push(_core().types.variableDeclaration("var", [_core().types.variableDeclarator(_core().types.identifier(ret), call)]));
+      placeholderPath = "declarations.0.init" + basePath;
+      index = this.body.length - 1;
+      this.buildHas(ret);
+    } else {
+      this.body.push(_core().types.expressionStatement(call));
+      placeholderPath = "expression" + basePath;
+      index = this.body.length - 1;
+    }
+
+    let callPath;
+
+    if (isSwitch) {
+      const _this$blockPath = this.blockPath,
+            parentPath = _this$blockPath.parentPath,
+            listKey = _this$blockPath.listKey,
+            key = _this$blockPath.key;
+      this.blockPath.replaceWithMultiple(this.body);
+      callPath = parentPath.get(listKey)[key + index];
+    } else {
+      block.body = this.body;
+      callPath = this.blockPath.get("body")[index];
+    }
+
+    const placeholder = callPath.get(placeholderPath);
+    let fnPath;
+
+    if (this.loop) {
+      const loopId = this.scope.generateUid("loop");
+      const p = this.loopPath.insertBefore(_core().types.variableDeclaration("var", [_core().types.variableDeclarator(_core().types.identifier(loopId), fn)]));
+      placeholder.replaceWith(_core().types.identifier(loopId));
+      fnPath = p[0].get("declarations.0.init");
+    } else {
+      placeholder.replaceWith(fn);
+      fnPath = placeholder;
+    }
+
+    fnPath.unwrapFunctionEnvironment();
+  }
+
+  addContinuations(fn) {
+    const state = {
+      reassignments: {},
+      returnStatements: [],
+      outsideReferences: this.outsideLetReferences
+    };
+    this.scope.traverse(fn, continuationVisitor, state);
+
+    for (let i = 0; i < fn.params.length; i++) {
+      const param = fn.params[i];
+      if (!state.reassignments[param.name]) continue;
+      const paramName = param.name;
+      const newParamName = this.scope.generateUid(param.name);
+      fn.params[i] = _core().types.identifier(newParamName);
+      this.scope.rename(paramName, newParamName, fn);
+      state.returnStatements.forEach(returnStatement => {
+        returnStatement.insertBefore(_core().types.expressionStatement(_core().types.assignmentExpression("=", _core().types.identifier(paramName), _core().types.identifier(newParamName))));
+      });
+      fn.body.body.push(_core().types.expressionStatement(_core().types.assignmentExpression("=", _core().types.identifier(paramName), _core().types.identifier(newParamName))));
+    }
+  }
+
+  getLetReferences() {
+    const block = this.block;
+    let declarators = [];
+
+    if (this.loop) {
+      const init = this.loop.left || this.loop.init;
+
+      if (isBlockScoped(init)) {
+        declarators.push(init);
+        (0, _extend().default)(this.outsideLetReferences, _core().types.getBindingIdentifiers(init));
+      }
+    }
+
+    const addDeclarationsFromChild = (path, node) => {
+      node = node || path.node;
+
+      if (_core().types.isClassDeclaration(node) || _core().types.isFunctionDeclaration(node) || isBlockScoped(node)) {
+        if (isBlockScoped(node)) {
+          convertBlockScopedToVar(path, node, block, this.scope);
+        }
+
+        declarators = declarators.concat(node.declarations || node);
+      }
+
+      if (_core().types.isLabeledStatement(node)) {
+        addDeclarationsFromChild(path.get("body"), node.body);
+      }
+    };
+
+    if (block.body) {
+      const declarPaths = this.blockPath.get("body");
+
+      for (let i = 0; i < block.body.length; i++) {
+        addDeclarationsFromChild(declarPaths[i]);
+      }
+    }
+
+    if (block.cases) {
+      const declarPaths = this.blockPath.get("cases");
+
+      for (let i = 0; i < block.cases.length; i++) {
+        const consequents = block.cases[i].consequent;
+
+        for (let j = 0; j < consequents.length; j++) {
+          const declar = consequents[j];
+          addDeclarationsFromChild(declarPaths[i], declar);
+        }
+      }
+    }
+
+    for (let i = 0; i < declarators.length; i++) {
+      const declar = declarators[i];
+
+      const keys = _core().types.getBindingIdentifiers(declar, false, true);
+
+      (0, _extend().default)(this.letReferences, keys);
+      this.hasLetReferences = true;
+    }
+
+    if (!this.hasLetReferences) return;
+    const state = {
+      letReferences: this.letReferences,
+      closurify: false,
+      loopDepth: 0,
+      tdzEnabled: this.tdzEnabled,
+      addHelper: name => this.addHelper(name)
+    };
+
+    if (isInLoop(this.blockPath)) {
+      state.loopDepth++;
+    }
+
+    this.blockPath.traverse(letReferenceBlockVisitor, state);
+    return state.closurify;
+  }
+
+  checkLoop() {
+    const state = {
+      hasBreakContinue: false,
+      ignoreLabeless: false,
+      inSwitchCase: false,
+      innerLabels: [],
+      hasReturn: false,
+      isLoop: !!this.loop,
+      map: {},
+      LOOP_IGNORE: Symbol()
+    };
+    this.blockPath.traverse(loopLabelVisitor, state);
+    this.blockPath.traverse(loopVisitor, state);
+    return state;
+  }
+
+  hoistVarDeclarations() {
+    this.blockPath.traverse(hoistVarDeclarationsVisitor, this);
+  }
+
+  pushDeclar(node) {
+    const declars = [];
+
+    const names = _core().types.getBindingIdentifiers(node);
+
+    for (const name in names) {
+      declars.push(_core().types.variableDeclarator(names[name]));
+    }
+
+    this.body.push(_core().types.variableDeclaration(node.kind, declars));
+    const replace = [];
+
+    for (let i = 0; i < node.declarations.length; i++) {
+      const declar = node.declarations[i];
+      if (!declar.init) continue;
+
+      const expr = _core().types.assignmentExpression("=", _core().types.cloneNode(declar.id), _core().types.cloneNode(declar.init));
+
+      replace.push(_core().types.inherits(expr, declar));
+    }
+
+    return replace;
+  }
+
+  buildHas(ret) {
+    const body = this.body;
+    let retCheck;
+    const has = this.has;
+    const cases = [];
+
+    if (has.hasReturn) {
+      retCheck = buildRetCheck({
+        RETURN: _core().types.identifier(ret)
+      });
+    }
+
+    if (has.hasBreakContinue) {
+      for (const key in has.map) {
+        cases.push(_core().types.switchCase(_core().types.stringLiteral(key), [has.map[key]]));
+      }
+
+      if (has.hasReturn) {
+        cases.push(_core().types.switchCase(null, [retCheck]));
+      }
+
+      if (cases.length === 1) {
+        const single = cases[0];
+        body.push(_core().types.ifStatement(_core().types.binaryExpression("===", _core().types.identifier(ret), single.test), single.consequent[0]));
+      } else {
+        if (this.loop) {
+          for (let i = 0; i < cases.length; i++) {
+            const caseConsequent = cases[i].consequent[0];
+
+            if (_core().types.isBreakStatement(caseConsequent) && !caseConsequent.label) {
+              if (!this.loopLabel) {
+                this.loopLabel = this.scope.generateUidIdentifier("loop");
+              }
+
+              caseConsequent.label = _core().types.cloneNode(this.loopLabel);
+            }
+          }
+        }
+
+        body.push(_core().types.switchStatement(_core().types.identifier(ret), cases));
+      }
+    } else {
+      if (has.hasReturn) {
+        body.push(retCheck);
+      }
+    }
+  }
+
+}
\ No newline at end of file
diff --git a/node_modules/@babel/plugin-transform-block-scoping/lib/tdz.js b/node_modules/@babel/plugin-transform-block-scoping/lib/tdz.js
new file mode 100644
index 00000000..df5b4d41
--- /dev/null
+++ b/node_modules/@babel/plugin-transform-block-scoping/lib/tdz.js
@@ -0,0 +1,96 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.visitor = void 0;
+
+function _core() {
+  const data = require("@babel/core");
+
+  _core = function _core() {
+    return data;
+  };
+
+  return data;
+}
+
+function getTDZStatus(refPath, bindingPath) {
+  const executionStatus = bindingPath._guessExecutionStatusRelativeTo(refPath);
+
+  if (executionStatus === "before") {
+    return "inside";
+  } else if (executionStatus === "after") {
+    return "outside";
+  } else {
+    return "maybe";
+  }
+}
+
+function buildTDZAssert(node, state) {
+  return _core().types.callExpression(state.addHelper("temporalRef"), [node, _core().types.stringLiteral(node.name)]);
+}
+
+function isReference(node, scope, state) {
+  const declared = state.letReferences[node.name];
+  if (!declared) return false;
+  return scope.getBindingIdentifier(node.name) === declared;
+}
+
+const visitor = {
+  ReferencedIdentifier(path, state) {
+    if (!state.tdzEnabled) return;
+    const node = path.node,
+          parent = path.parent,
+          scope = path.scope;
+    if (path.parentPath.isFor({
+      left: node
+    })) return;
+    if (!isReference(node, scope, state)) return;
+    const bindingPath = scope.getBinding(node.name).path;
+    if (bindingPath.isFunctionDeclaration()) return;
+    const status = getTDZStatus(path, bindingPath);
+    if (status === "inside") return;
+
+    if (status === "maybe") {
+      const assert = buildTDZAssert(node, state);
+      bindingPath.parent._tdzThis = true;
+      path.skip();
+
+      if (path.parentPath.isUpdateExpression()) {
+        if (parent._ignoreBlockScopingTDZ) return;
+        path.parentPath.replaceWith(_core().types.sequenceExpression([assert, parent]));
+      } else {
+        path.replaceWith(assert);
+      }
+    } else if (status === "outside") {
+      path.replaceWith(_core().types.throwStatement(_core().types.inherits(_core().types.newExpression(_core().types.identifier("ReferenceError"), [_core().types.stringLiteral(`${node.name} is not defined - temporal dead zone`)]), node)));
+    }
+  },
+
+  AssignmentExpression: {
+    exit(path, state) {
+      if (!state.tdzEnabled) return;
+      const node = path.node;
+      if (node._ignoreBlockScopingTDZ) return;
+      const nodes = [];
+      const ids = path.getBindingIdentifiers();
+
+      for (const name in ids) {
+        const id = ids[name];
+
+        if (isReference(id, path.scope, state)) {
+          nodes.push(buildTDZAssert(id, state));
+        }
+      }
+
+      if (nodes.length) {
+        node._ignoreBlockScopingTDZ = true;
+        nodes.push(node);
+        path.replaceWithMultiple(nodes.map(_core().types.expressionStatement));
+      }
+    }
+
+  }
+};
+exports.visitor = visitor;
\ No newline at end of file
diff --git a/node_modules/@babel/plugin-transform-block-scoping/package.json b/node_modules/@babel/plugin-transform-block-scoping/package.json
new file mode 100644
index 00000000..c23da85b
--- /dev/null
+++ b/node_modules/@babel/plugin-transform-block-scoping/package.json
@@ -0,0 +1,22 @@
+{
+  "name": "@babel/plugin-transform-block-scoping",
+  "version": "7.0.0-beta.47",
+  "description": "Compile ES2015 block scoping (const and let) to ES5",
+  "repository": "https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-block-scoping",
+  "license": "MIT",
+  "main": "lib/index.js",
+  "dependencies": {
+    "@babel/helper-plugin-utils": "7.0.0-beta.47",
+    "lodash": "^4.17.5"
+  },
+  "keywords": [
+    "babel-plugin"
+  ],
+  "peerDependencies": {
+    "@babel/core": "7.0.0-beta.47"
+  },
+  "devDependencies": {
+    "@babel/core": "7.0.0-beta.47",
+    "@babel/helper-plugin-test-runner": "7.0.0-beta.47"
+  }
+}