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diff --git a/node_modules/sucrase/dist/esm/parser/tokenizer/index.js b/node_modules/sucrase/dist/esm/parser/tokenizer/index.js
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+/* eslint max-len: 0 */
+
+import {input, isFlowEnabled, state} from "../traverser/base";
+import {unexpected} from "../traverser/util";
+import {charCodes} from "../util/charcodes";
+import {IS_IDENTIFIER_CHAR, IS_IDENTIFIER_START} from "../util/identifier";
+import {IS_WHITESPACE, skipWhiteSpace} from "../util/whitespace";
+import {ContextualKeyword} from "./keywords";
+import readWord from "./readWord";
+import { TokenType as tt} from "./types";
+
+export var IdentifierRole; (function (IdentifierRole) {
+  const Access = 0; IdentifierRole[IdentifierRole["Access"] = Access] = "Access";
+  const ExportAccess = Access + 1; IdentifierRole[IdentifierRole["ExportAccess"] = ExportAccess] = "ExportAccess";
+  const TopLevelDeclaration = ExportAccess + 1; IdentifierRole[IdentifierRole["TopLevelDeclaration"] = TopLevelDeclaration] = "TopLevelDeclaration";
+  const FunctionScopedDeclaration = TopLevelDeclaration + 1; IdentifierRole[IdentifierRole["FunctionScopedDeclaration"] = FunctionScopedDeclaration] = "FunctionScopedDeclaration";
+  const BlockScopedDeclaration = FunctionScopedDeclaration + 1; IdentifierRole[IdentifierRole["BlockScopedDeclaration"] = BlockScopedDeclaration] = "BlockScopedDeclaration";
+  const ObjectShorthandTopLevelDeclaration = BlockScopedDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthandTopLevelDeclaration"] = ObjectShorthandTopLevelDeclaration] = "ObjectShorthandTopLevelDeclaration";
+  const ObjectShorthandFunctionScopedDeclaration = ObjectShorthandTopLevelDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthandFunctionScopedDeclaration"] = ObjectShorthandFunctionScopedDeclaration] = "ObjectShorthandFunctionScopedDeclaration";
+  const ObjectShorthandBlockScopedDeclaration = ObjectShorthandFunctionScopedDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthandBlockScopedDeclaration"] = ObjectShorthandBlockScopedDeclaration] = "ObjectShorthandBlockScopedDeclaration";
+  const ObjectShorthand = ObjectShorthandBlockScopedDeclaration + 1; IdentifierRole[IdentifierRole["ObjectShorthand"] = ObjectShorthand] = "ObjectShorthand";
+  // Any identifier bound in an import statement, e.g. both A and b from
+  // `import A, * as b from 'A';`
+  const ImportDeclaration = ObjectShorthand + 1; IdentifierRole[IdentifierRole["ImportDeclaration"] = ImportDeclaration] = "ImportDeclaration";
+  const ObjectKey = ImportDeclaration + 1; IdentifierRole[IdentifierRole["ObjectKey"] = ObjectKey] = "ObjectKey";
+  // The `foo` in `import {foo as bar} from "./abc";`.
+  const ImportAccess = ObjectKey + 1; IdentifierRole[IdentifierRole["ImportAccess"] = ImportAccess] = "ImportAccess";
+})(IdentifierRole || (IdentifierRole = {}));
+
+/**
+ * Extra information on jsxTagStart tokens, used to determine which of the three
+ * jsx functions are called in the automatic transform.
+ */
+export var JSXRole; (function (JSXRole) {
+  // The element is self-closing or has a body that resolves to empty. We
+  // shouldn't emit children at all in this case.
+  const NoChildren = 0; JSXRole[JSXRole["NoChildren"] = NoChildren] = "NoChildren";
+  // The element has a single explicit child, which might still be an arbitrary
+  // expression like an array. We should emit that expression as the children.
+  const OneChild = NoChildren + 1; JSXRole[JSXRole["OneChild"] = OneChild] = "OneChild";
+  // The element has at least two explicitly-specified children or has spread
+  // children, so child positions are assumed to be "static". We should wrap
+  // these children in an array.
+  const StaticChildren = OneChild + 1; JSXRole[JSXRole["StaticChildren"] = StaticChildren] = "StaticChildren";
+  // The element has a prop named "key" after a prop spread, so we should fall
+  // back to the createElement function.
+  const KeyAfterPropSpread = StaticChildren + 1; JSXRole[JSXRole["KeyAfterPropSpread"] = KeyAfterPropSpread] = "KeyAfterPropSpread";
+})(JSXRole || (JSXRole = {}));
+
+export function isDeclaration(token) {
+  const role = token.identifierRole;
+  return (
+    role === IdentifierRole.TopLevelDeclaration ||
+    role === IdentifierRole.FunctionScopedDeclaration ||
+    role === IdentifierRole.BlockScopedDeclaration ||
+    role === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
+    role === IdentifierRole.ObjectShorthandFunctionScopedDeclaration ||
+    role === IdentifierRole.ObjectShorthandBlockScopedDeclaration
+  );
+}
+
+export function isNonTopLevelDeclaration(token) {
+  const role = token.identifierRole;
+  return (
+    role === IdentifierRole.FunctionScopedDeclaration ||
+    role === IdentifierRole.BlockScopedDeclaration ||
+    role === IdentifierRole.ObjectShorthandFunctionScopedDeclaration ||
+    role === IdentifierRole.ObjectShorthandBlockScopedDeclaration
+  );
+}
+
+export function isTopLevelDeclaration(token) {
+  const role = token.identifierRole;
+  return (
+    role === IdentifierRole.TopLevelDeclaration ||
+    role === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
+    role === IdentifierRole.ImportDeclaration
+  );
+}
+
+export function isBlockScopedDeclaration(token) {
+  const role = token.identifierRole;
+  // Treat top-level declarations as block scope since the distinction doesn't matter here.
+  return (
+    role === IdentifierRole.TopLevelDeclaration ||
+    role === IdentifierRole.BlockScopedDeclaration ||
+    role === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
+    role === IdentifierRole.ObjectShorthandBlockScopedDeclaration
+  );
+}
+
+export function isFunctionScopedDeclaration(token) {
+  const role = token.identifierRole;
+  return (
+    role === IdentifierRole.FunctionScopedDeclaration ||
+    role === IdentifierRole.ObjectShorthandFunctionScopedDeclaration
+  );
+}
+
+export function isObjectShorthandDeclaration(token) {
+  return (
+    token.identifierRole === IdentifierRole.ObjectShorthandTopLevelDeclaration ||
+    token.identifierRole === IdentifierRole.ObjectShorthandBlockScopedDeclaration ||
+    token.identifierRole === IdentifierRole.ObjectShorthandFunctionScopedDeclaration
+  );
+}
+
+// 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.
+export class Token {
+  constructor() {
+    this.type = state.type;
+    this.contextualKeyword = state.contextualKeyword;
+    this.start = state.start;
+    this.end = state.end;
+    this.scopeDepth = state.scopeDepth;
+    this.isType = state.isType;
+    this.identifierRole = null;
+    this.jsxRole = null;
+    this.shadowsGlobal = false;
+    this.isAsyncOperation = false;
+    this.contextId = null;
+    this.rhsEndIndex = null;
+    this.isExpression = false;
+    this.numNullishCoalesceStarts = 0;
+    this.numNullishCoalesceEnds = 0;
+    this.isOptionalChainStart = false;
+    this.isOptionalChainEnd = false;
+    this.subscriptStartIndex = null;
+    this.nullishStartIndex = null;
+  }
+
+  
+  
+  
+  
+  
+  
+  
+  
+  // Initially false for all tokens, then may be computed in a follow-up step that does scope
+  // analysis.
+  
+  // Initially false for all tokens, but may be set during transform to mark it as containing an
+  // await operation.
+  
+  
+  // For assignments, the index of the RHS. For export tokens, the end of the export.
+  
+  // For class tokens, records if the class is a class expression or a class statement.
+  
+  // Number of times to insert a `nullishCoalesce(` snippet before this token.
+  
+  // Number of times to insert a `)` snippet after this token.
+  
+  // If true, insert an `optionalChain([` snippet before this token.
+  
+  // If true, insert a `])` snippet after this token.
+  
+  // Tag for `.`, `?.`, `[`, `?.[`, `(`, and `?.(` to denote the "root" token for this
+  // subscript chain. This can be used to determine if this chain is an optional chain.
+  
+  // Tag for `??` operators to denote the root token for this nullish coalescing call.
+  
+}
+
+// ## Tokenizer
+
+// Move to the next token
+export function next() {
+  state.tokens.push(new Token());
+  nextToken();
+}
+
+// Call instead of next when inside a template, since that needs to be handled differently.
+export function nextTemplateToken() {
+  state.tokens.push(new Token());
+  state.start = state.pos;
+  readTmplToken();
+}
+
+// The tokenizer never parses regexes by default. Instead, the parser is responsible for
+// instructing it to parse a regex when we see a slash at the start of an expression.
+export function retokenizeSlashAsRegex() {
+  if (state.type === tt.assign) {
+    --state.pos;
+  }
+  readRegexp();
+}
+
+export function pushTypeContext(existingTokensInType) {
+  for (let i = state.tokens.length - existingTokensInType; i < state.tokens.length; i++) {
+    state.tokens[i].isType = true;
+  }
+  const oldIsType = state.isType;
+  state.isType = true;
+  return oldIsType;
+}
+
+export function popTypeContext(oldIsType) {
+  state.isType = oldIsType;
+}
+
+export function eat(type) {
+  if (match(type)) {
+    next();
+    return true;
+  } else {
+    return false;
+  }
+}
+
+export function eatTypeToken(tokenType) {
+  const oldIsType = state.isType;
+  state.isType = true;
+  eat(tokenType);
+  state.isType = oldIsType;
+}
+
+export function match(type) {
+  return state.type === type;
+}
+
+export function lookaheadType() {
+  const snapshot = state.snapshot();
+  next();
+  const type = state.type;
+  state.restoreFromSnapshot(snapshot);
+  return type;
+}
+
+export class TypeAndKeyword {
+  
+  
+  constructor(type, contextualKeyword) {
+    this.type = type;
+    this.contextualKeyword = contextualKeyword;
+  }
+}
+
+export function lookaheadTypeAndKeyword() {
+  const snapshot = state.snapshot();
+  next();
+  const type = state.type;
+  const contextualKeyword = state.contextualKeyword;
+  state.restoreFromSnapshot(snapshot);
+  return new TypeAndKeyword(type, contextualKeyword);
+}
+
+export function nextTokenStart() {
+  return nextTokenStartSince(state.pos);
+}
+
+export function nextTokenStartSince(pos) {
+  skipWhiteSpace.lastIndex = pos;
+  const skip = skipWhiteSpace.exec(input);
+  return pos + skip[0].length;
+}
+
+export function lookaheadCharCode() {
+  return input.charCodeAt(nextTokenStart());
+}
+
+// Read a single token, updating the parser object's token-related
+// properties.
+export function nextToken() {
+  skipSpace();
+  state.start = state.pos;
+  if (state.pos >= input.length) {
+    const tokens = state.tokens;
+    // We normally run past the end a bit, but if we're way past the end, avoid an infinite loop.
+    // Also check the token positions rather than the types since sometimes we rewrite the token
+    // type to something else.
+    if (
+      tokens.length >= 2 &&
+      tokens[tokens.length - 1].start >= input.length &&
+      tokens[tokens.length - 2].start >= input.length
+    ) {
+      unexpected("Unexpectedly reached the end of input.");
+    }
+    finishToken(tt.eof);
+    return;
+  }
+  readToken(input.charCodeAt(state.pos));
+}
+
+function readToken(code) {
+  // Identifier or keyword. '\uXXXX' sequences are allowed in
+  // identifiers, so '\' also dispatches to that.
+  if (
+    IS_IDENTIFIER_START[code] ||
+    code === charCodes.backslash ||
+    (code === charCodes.atSign && input.charCodeAt(state.pos + 1) === charCodes.atSign)
+  ) {
+    readWord();
+  } else {
+    getTokenFromCode(code);
+  }
+}
+
+function skipBlockComment() {
+  while (
+    input.charCodeAt(state.pos) !== charCodes.asterisk ||
+    input.charCodeAt(state.pos + 1) !== charCodes.slash
+  ) {
+    state.pos++;
+    if (state.pos > input.length) {
+      unexpected("Unterminated comment", state.pos - 2);
+      return;
+    }
+  }
+  state.pos += 2;
+}
+
+export function skipLineComment(startSkip) {
+  let ch = input.charCodeAt((state.pos += startSkip));
+  if (state.pos < input.length) {
+    while (
+      ch !== charCodes.lineFeed &&
+      ch !== charCodes.carriageReturn &&
+      ch !== charCodes.lineSeparator &&
+      ch !== charCodes.paragraphSeparator &&
+      ++state.pos < input.length
+    ) {
+      ch = input.charCodeAt(state.pos);
+    }
+  }
+}
+
+// Called at the start of the parse and after every token. Skips
+// whitespace and comments.
+export function skipSpace() {
+  while (state.pos < input.length) {
+    const ch = input.charCodeAt(state.pos);
+    switch (ch) {
+      case charCodes.carriageReturn:
+        if (input.charCodeAt(state.pos + 1) === charCodes.lineFeed) {
+          ++state.pos;
+        }
+
+      case charCodes.lineFeed:
+      case charCodes.lineSeparator:
+      case charCodes.paragraphSeparator:
+        ++state.pos;
+        break;
+
+      case charCodes.slash:
+        switch (input.charCodeAt(state.pos + 1)) {
+          case charCodes.asterisk:
+            state.pos += 2;
+            skipBlockComment();
+            break;
+
+          case charCodes.slash:
+            skipLineComment(2);
+            break;
+
+          default:
+            return;
+        }
+        break;
+
+      default:
+        if (IS_WHITESPACE[ch]) {
+          ++state.pos;
+        } else {
+          return;
+        }
+    }
+  }
+}
+
+// Called at the end of every token. Sets various fields, and skips the space after the token, so
+// that the next one's `start` will point at the right position.
+export function finishToken(
+  type,
+  contextualKeyword = ContextualKeyword.NONE,
+) {
+  state.end = state.pos;
+  state.type = type;
+  state.contextualKeyword = contextualKeyword;
+}
+
+// ### 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.
+function readToken_dot() {
+  const nextChar = input.charCodeAt(state.pos + 1);
+  if (nextChar >= charCodes.digit0 && nextChar <= charCodes.digit9) {
+    readNumber(true);
+    return;
+  }
+
+  if (nextChar === charCodes.dot && input.charCodeAt(state.pos + 2) === charCodes.dot) {
+    state.pos += 3;
+    finishToken(tt.ellipsis);
+  } else {
+    ++state.pos;
+    finishToken(tt.dot);
+  }
+}
+
+function readToken_slash() {
+  const nextChar = input.charCodeAt(state.pos + 1);
+  if (nextChar === charCodes.equalsTo) {
+    finishOp(tt.assign, 2);
+  } else {
+    finishOp(tt.slash, 1);
+  }
+}
+
+function readToken_mult_modulo(code) {
+  // '%*'
+  let tokenType = code === charCodes.asterisk ? tt.star : tt.modulo;
+  let width = 1;
+  let nextChar = input.charCodeAt(state.pos + 1);
+
+  // Exponentiation operator **
+  if (code === charCodes.asterisk && nextChar === charCodes.asterisk) {
+    width++;
+    nextChar = input.charCodeAt(state.pos + 2);
+    tokenType = tt.exponent;
+  }
+
+  // Match *= or %=, disallowing *=> which can be valid in flow.
+  if (
+    nextChar === charCodes.equalsTo &&
+    input.charCodeAt(state.pos + 2) !== charCodes.greaterThan
+  ) {
+    width++;
+    tokenType = tt.assign;
+  }
+
+  finishOp(tokenType, width);
+}
+
+function readToken_pipe_amp(code) {
+  // '|&'
+  const nextChar = input.charCodeAt(state.pos + 1);
+
+  if (nextChar === code) {
+    if (input.charCodeAt(state.pos + 2) === charCodes.equalsTo) {
+      // ||= or &&=
+      finishOp(tt.assign, 3);
+    } else {
+      // || or &&
+      finishOp(code === charCodes.verticalBar ? tt.logicalOR : tt.logicalAND, 2);
+    }
+    return;
+  }
+
+  if (code === charCodes.verticalBar) {
+    // '|>'
+    if (nextChar === charCodes.greaterThan) {
+      finishOp(tt.pipeline, 2);
+      return;
+    } else if (nextChar === charCodes.rightCurlyBrace && isFlowEnabled) {
+      // '|}'
+      finishOp(tt.braceBarR, 2);
+      return;
+    }
+  }
+
+  if (nextChar === charCodes.equalsTo) {
+    finishOp(tt.assign, 2);
+    return;
+  }
+
+  finishOp(code === charCodes.verticalBar ? tt.bitwiseOR : tt.bitwiseAND, 1);
+}
+
+function readToken_caret() {
+  // '^'
+  const nextChar = input.charCodeAt(state.pos + 1);
+  if (nextChar === charCodes.equalsTo) {
+    finishOp(tt.assign, 2);
+  } else {
+    finishOp(tt.bitwiseXOR, 1);
+  }
+}
+
+function readToken_plus_min(code) {
+  // '+-'
+  const nextChar = input.charCodeAt(state.pos + 1);
+
+  if (nextChar === code) {
+    // Tentatively call this a prefix operator, but it might be changed to postfix later.
+    finishOp(tt.preIncDec, 2);
+    return;
+  }
+
+  if (nextChar === charCodes.equalsTo) {
+    finishOp(tt.assign, 2);
+  } else if (code === charCodes.plusSign) {
+    finishOp(tt.plus, 1);
+  } else {
+    finishOp(tt.minus, 1);
+  }
+}
+
+function readToken_lt() {
+  const nextChar = input.charCodeAt(state.pos + 1);
+
+  if (nextChar === charCodes.lessThan) {
+    if (input.charCodeAt(state.pos + 2) === charCodes.equalsTo) {
+      finishOp(tt.assign, 3);
+      return;
+    }
+    // We see <<, but need to be really careful about whether to treat it as a
+    // true left-shift or as two < tokens.
+    if (state.isType) {
+      // Within a type, << might come up in a snippet like `Array<<T>() => void>`,
+      // so treat it as two < tokens. Importantly, this should only override <<
+      // rather than other tokens like <= . If we treated <= as < in a type
+      // context, then the snippet `a as T <= 1` would incorrectly start parsing
+      // a type argument on T. We don't need to worry about `a as T << 1`
+      // because TypeScript disallows that syntax.
+      finishOp(tt.lessThan, 1);
+    } else {
+      // Outside a type, this might be a true left-shift operator, or it might
+      // still be two open-type-arg tokens, such as in `f<<T>() => void>()`. We
+      // look at the token while considering the `f`, so we don't yet know that
+      // we're in a type context. In this case, we initially tokenize as a
+      // left-shift and correct after-the-fact as necessary in
+      // tsParseTypeArgumentsWithPossibleBitshift .
+      finishOp(tt.bitShiftL, 2);
+    }
+    return;
+  }
+
+  if (nextChar === charCodes.equalsTo) {
+    // <=
+    finishOp(tt.relationalOrEqual, 2);
+  } else {
+    finishOp(tt.lessThan, 1);
+  }
+}
+
+function readToken_gt() {
+  if (state.isType) {
+    // Avoid right-shift for things like `Array<Array<string>>` and
+    // greater-than-or-equal for things like `const a: Array<number>=[];`.
+    finishOp(tt.greaterThan, 1);
+    return;
+  }
+
+  const nextChar = input.charCodeAt(state.pos + 1);
+
+  if (nextChar === charCodes.greaterThan) {
+    const size = input.charCodeAt(state.pos + 2) === charCodes.greaterThan ? 3 : 2;
+    if (input.charCodeAt(state.pos + size) === charCodes.equalsTo) {
+      finishOp(tt.assign, size + 1);
+      return;
+    }
+    finishOp(tt.bitShiftR, size);
+    return;
+  }
+
+  if (nextChar === charCodes.equalsTo) {
+    // >=
+    finishOp(tt.relationalOrEqual, 2);
+  } else {
+    finishOp(tt.greaterThan, 1);
+  }
+}
+
+/**
+ * Reinterpret a possible > token when transitioning from a type to a non-type
+ * context.
+ *
+ * This comes up in two situations where >= needs to be treated as one token:
+ * - After an `as` expression, like in the code `a as T >= 1`.
+ * - In a type argument in an expression context, e.g. `f(a < b, c >= d)`, we
+ *   need to see the token as >= so that we get an error and backtrack to
+ *   normal expression parsing.
+ *
+ * Other situations require >= to be seen as two tokens, e.g.
+ * `const x: Array<T>=[];`, so it's important to treat > as its own token in
+ * typical type parsing situations.
+ */
+export function rescan_gt() {
+  if (state.type === tt.greaterThan) {
+    state.pos -= 1;
+    readToken_gt();
+  }
+}
+
+function readToken_eq_excl(code) {
+  // '=!'
+  const nextChar = input.charCodeAt(state.pos + 1);
+  if (nextChar === charCodes.equalsTo) {
+    finishOp(tt.equality, input.charCodeAt(state.pos + 2) === charCodes.equalsTo ? 3 : 2);
+    return;
+  }
+  if (code === charCodes.equalsTo && nextChar === charCodes.greaterThan) {
+    // '=>'
+    state.pos += 2;
+    finishToken(tt.arrow);
+    return;
+  }
+  finishOp(code === charCodes.equalsTo ? tt.eq : tt.bang, 1);
+}
+
+function readToken_question() {
+  // '?'
+  const nextChar = input.charCodeAt(state.pos + 1);
+  const nextChar2 = input.charCodeAt(state.pos + 2);
+  if (
+    nextChar === charCodes.questionMark &&
+    // In Flow (but not TypeScript), ??string is a valid type that should be
+    // tokenized as two individual ? tokens.
+    !(isFlowEnabled && state.isType)
+  ) {
+    if (nextChar2 === charCodes.equalsTo) {
+      // '??='
+      finishOp(tt.assign, 3);
+    } else {
+      // '??'
+      finishOp(tt.nullishCoalescing, 2);
+    }
+  } else if (
+    nextChar === charCodes.dot &&
+    !(nextChar2 >= charCodes.digit0 && nextChar2 <= charCodes.digit9)
+  ) {
+    // '.' not followed by a number
+    state.pos += 2;
+    finishToken(tt.questionDot);
+  } else {
+    ++state.pos;
+    finishToken(tt.question);
+  }
+}
+
+export function getTokenFromCode(code) {
+  switch (code) {
+    case charCodes.numberSign:
+      ++state.pos;
+      finishToken(tt.hash);
+      return;
+
+    // The interpretation of a dot depends on whether it is followed
+    // by a digit or another two dots.
+
+    case charCodes.dot:
+      readToken_dot();
+      return;
+
+    // Punctuation tokens.
+    case charCodes.leftParenthesis:
+      ++state.pos;
+      finishToken(tt.parenL);
+      return;
+    case charCodes.rightParenthesis:
+      ++state.pos;
+      finishToken(tt.parenR);
+      return;
+    case charCodes.semicolon:
+      ++state.pos;
+      finishToken(tt.semi);
+      return;
+    case charCodes.comma:
+      ++state.pos;
+      finishToken(tt.comma);
+      return;
+    case charCodes.leftSquareBracket:
+      ++state.pos;
+      finishToken(tt.bracketL);
+      return;
+    case charCodes.rightSquareBracket:
+      ++state.pos;
+      finishToken(tt.bracketR);
+      return;
+
+    case charCodes.leftCurlyBrace:
+      if (isFlowEnabled && input.charCodeAt(state.pos + 1) === charCodes.verticalBar) {
+        finishOp(tt.braceBarL, 2);
+      } else {
+        ++state.pos;
+        finishToken(tt.braceL);
+      }
+      return;
+
+    case charCodes.rightCurlyBrace:
+      ++state.pos;
+      finishToken(tt.braceR);
+      return;
+
+    case charCodes.colon:
+      if (input.charCodeAt(state.pos + 1) === charCodes.colon) {
+        finishOp(tt.doubleColon, 2);
+      } else {
+        ++state.pos;
+        finishToken(tt.colon);
+      }
+      return;
+
+    case charCodes.questionMark:
+      readToken_question();
+      return;
+    case charCodes.atSign:
+      ++state.pos;
+      finishToken(tt.at);
+      return;
+
+    case charCodes.graveAccent:
+      ++state.pos;
+      finishToken(tt.backQuote);
+      return;
+
+    case charCodes.digit0: {
+      const nextChar = input.charCodeAt(state.pos + 1);
+      // '0x', '0X', '0o', '0O', '0b', '0B'
+      if (
+        nextChar === charCodes.lowercaseX ||
+        nextChar === charCodes.uppercaseX ||
+        nextChar === charCodes.lowercaseO ||
+        nextChar === charCodes.uppercaseO ||
+        nextChar === charCodes.lowercaseB ||
+        nextChar === charCodes.uppercaseB
+      ) {
+        readRadixNumber();
+        return;
+      }
+    }
+    // Anything else beginning with a digit is an integer, octal
+    // number, or float.
+    case charCodes.digit1:
+    case charCodes.digit2:
+    case charCodes.digit3:
+    case charCodes.digit4:
+    case charCodes.digit5:
+    case charCodes.digit6:
+    case charCodes.digit7:
+    case charCodes.digit8:
+    case charCodes.digit9:
+      readNumber(false);
+      return;
+
+    // Quotes produce strings.
+    case charCodes.quotationMark:
+    case charCodes.apostrophe:
+      readString(code);
+      return;
+
+    // Operators are parsed inline in tiny state machines. '=' (charCodes.equalsTo) 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 charCodes.slash:
+      readToken_slash();
+      return;
+
+    case charCodes.percentSign:
+    case charCodes.asterisk:
+      readToken_mult_modulo(code);
+      return;
+
+    case charCodes.verticalBar:
+    case charCodes.ampersand:
+      readToken_pipe_amp(code);
+      return;
+
+    case charCodes.caret:
+      readToken_caret();
+      return;
+
+    case charCodes.plusSign:
+    case charCodes.dash:
+      readToken_plus_min(code);
+      return;
+
+    case charCodes.lessThan:
+      readToken_lt();
+      return;
+
+    case charCodes.greaterThan:
+      readToken_gt();
+      return;
+
+    case charCodes.equalsTo:
+    case charCodes.exclamationMark:
+      readToken_eq_excl(code);
+      return;
+
+    case charCodes.tilde:
+      finishOp(tt.tilde, 1);
+      return;
+
+    default:
+      break;
+  }
+
+  unexpected(`Unexpected character '${String.fromCharCode(code)}'`, state.pos);
+}
+
+function finishOp(type, size) {
+  state.pos += size;
+  finishToken(type);
+}
+
+function readRegexp() {
+  const start = state.pos;
+  let escaped = false;
+  let inClass = false;
+  for (;;) {
+    if (state.pos >= input.length) {
+      unexpected("Unterminated regular expression", start);
+      return;
+    }
+    const code = input.charCodeAt(state.pos);
+    if (escaped) {
+      escaped = false;
+    } else {
+      if (code === charCodes.leftSquareBracket) {
+        inClass = true;
+      } else if (code === charCodes.rightSquareBracket && inClass) {
+        inClass = false;
+      } else if (code === charCodes.slash && !inClass) {
+        break;
+      }
+      escaped = code === charCodes.backslash;
+    }
+    ++state.pos;
+  }
+  ++state.pos;
+  // Need to use `skipWord` because '\uXXXX' sequences are allowed here (don't ask).
+  skipWord();
+
+  finishToken(tt.regexp);
+}
+
+/**
+ * Read a decimal integer. Note that this can't be unified with the similar code
+ * in readRadixNumber (which also handles hex digits) because "e" needs to be
+ * the end of the integer so that we can properly handle scientific notation.
+ */
+function readInt() {
+  while (true) {
+    const code = input.charCodeAt(state.pos);
+    if ((code >= charCodes.digit0 && code <= charCodes.digit9) || code === charCodes.underscore) {
+      state.pos++;
+    } else {
+      break;
+    }
+  }
+}
+
+function readRadixNumber() {
+  state.pos += 2; // 0x
+
+  // Walk to the end of the number, allowing hex digits.
+  while (true) {
+    const code = input.charCodeAt(state.pos);
+    if (
+      (code >= charCodes.digit0 && code <= charCodes.digit9) ||
+      (code >= charCodes.lowercaseA && code <= charCodes.lowercaseF) ||
+      (code >= charCodes.uppercaseA && code <= charCodes.uppercaseF) ||
+      code === charCodes.underscore
+    ) {
+      state.pos++;
+    } else {
+      break;
+    }
+  }
+
+  const nextChar = input.charCodeAt(state.pos);
+  if (nextChar === charCodes.lowercaseN) {
+    ++state.pos;
+    finishToken(tt.bigint);
+  } else {
+    finishToken(tt.num);
+  }
+}
+
+// Read an integer, octal integer, or floating-point number.
+function readNumber(startsWithDot) {
+  let isBigInt = false;
+  let isDecimal = false;
+
+  if (!startsWithDot) {
+    readInt();
+  }
+
+  let nextChar = input.charCodeAt(state.pos);
+  if (nextChar === charCodes.dot) {
+    ++state.pos;
+    readInt();
+    nextChar = input.charCodeAt(state.pos);
+  }
+
+  if (nextChar === charCodes.uppercaseE || nextChar === charCodes.lowercaseE) {
+    nextChar = input.charCodeAt(++state.pos);
+    if (nextChar === charCodes.plusSign || nextChar === charCodes.dash) {
+      ++state.pos;
+    }
+    readInt();
+    nextChar = input.charCodeAt(state.pos);
+  }
+
+  if (nextChar === charCodes.lowercaseN) {
+    ++state.pos;
+    isBigInt = true;
+  } else if (nextChar === charCodes.lowercaseM) {
+    ++state.pos;
+    isDecimal = true;
+  }
+
+  if (isBigInt) {
+    finishToken(tt.bigint);
+    return;
+  }
+
+  if (isDecimal) {
+    finishToken(tt.decimal);
+    return;
+  }
+
+  finishToken(tt.num);
+}
+
+function readString(quote) {
+  state.pos++;
+  for (;;) {
+    if (state.pos >= input.length) {
+      unexpected("Unterminated string constant");
+      return;
+    }
+    const ch = input.charCodeAt(state.pos);
+    if (ch === charCodes.backslash) {
+      state.pos++;
+    } else if (ch === quote) {
+      break;
+    }
+    state.pos++;
+  }
+  state.pos++;
+  finishToken(tt.string);
+}
+
+// Reads template string tokens.
+function readTmplToken() {
+  for (;;) {
+    if (state.pos >= input.length) {
+      unexpected("Unterminated template");
+      return;
+    }
+    const ch = input.charCodeAt(state.pos);
+    if (
+      ch === charCodes.graveAccent ||
+      (ch === charCodes.dollarSign && input.charCodeAt(state.pos + 1) === charCodes.leftCurlyBrace)
+    ) {
+      if (state.pos === state.start && match(tt.template)) {
+        if (ch === charCodes.dollarSign) {
+          state.pos += 2;
+          finishToken(tt.dollarBraceL);
+          return;
+        } else {
+          ++state.pos;
+          finishToken(tt.backQuote);
+          return;
+        }
+      }
+      finishToken(tt.template);
+      return;
+    }
+    if (ch === charCodes.backslash) {
+      state.pos++;
+    }
+    state.pos++;
+  }
+}
+
+// Skip to the end of the current word. Note that this is the same as the snippet at the end of
+// readWord, but calling skipWord from readWord seems to slightly hurt performance from some rough
+// measurements.
+export function skipWord() {
+  while (state.pos < input.length) {
+    const ch = input.charCodeAt(state.pos);
+    if (IS_IDENTIFIER_CHAR[ch]) {
+      state.pos++;
+    } else if (ch === charCodes.backslash) {
+      // \u
+      state.pos += 2;
+      if (input.charCodeAt(state.pos) === charCodes.leftCurlyBrace) {
+        while (
+          state.pos < input.length &&
+          input.charCodeAt(state.pos) !== charCodes.rightCurlyBrace
+        ) {
+          state.pos++;
+        }
+        state.pos++;
+      }
+    } else {
+      break;
+    }
+  }
+}