// Generated by CoffeeScript 2.3.2
(function() {
  // The CoffeeScript Lexer. Uses a series of token-matching regexes to attempt
  // matches against the beginning of the source code. When a match is found,
  // a token is produced, we consume the match, and start again. Tokens are in the
  // form:

  //     [tag, value, locationData]

  // where locationData is {first_line, first_column, last_line, last_column}, which is a
  // format that can be fed directly into [Jison](https://github.com/zaach/jison).  These
  // are read by jison in the `parser.lexer` function defined in coffeescript.coffee.
  var BOM, BOOL, CALLABLE, CODE, COFFEE_ALIASES, COFFEE_ALIAS_MAP, COFFEE_KEYWORDS, COMMENT, COMPARABLE_LEFT_SIDE, COMPARE, COMPOUND_ASSIGN, CSX_ATTRIBUTE, CSX_FRAGMENT_IDENTIFIER, CSX_IDENTIFIER, CSX_INTERPOLATION, HERECOMMENT_ILLEGAL, HEREDOC_DOUBLE, HEREDOC_INDENT, HEREDOC_SINGLE, HEREGEX, HEREGEX_OMIT, HERE_JSTOKEN, IDENTIFIER, INDENTABLE_CLOSERS, INDEXABLE, INSIDE_CSX, INVERSES, JSTOKEN, JS_KEYWORDS, LEADING_BLANK_LINE, LINE_BREAK, LINE_CONTINUER, Lexer, MATH, MULTI_DENT, NOT_REGEX, NUMBER, OPERATOR, POSSIBLY_DIVISION, REGEX, REGEX_FLAGS, REGEX_ILLEGAL, REGEX_INVALID_ESCAPE, RELATION, RESERVED, Rewriter, SHIFT, SIMPLE_STRING_OMIT, STRICT_PROSCRIBED, STRING_DOUBLE, STRING_INVALID_ESCAPE, STRING_OMIT, STRING_SINGLE, STRING_START, TRAILING_BLANK_LINE, TRAILING_SPACES, UNARY, UNARY_MATH, UNFINISHED, UNICODE_CODE_POINT_ESCAPE, VALID_FLAGS, WHITESPACE, attachCommentsToNode, compact, count, invertLiterate, isForFrom, isUnassignable, key, locationDataToString, merge, repeat, starts, throwSyntaxError,
    indexOf = [].indexOf,
    slice = [].slice;

  ({Rewriter, INVERSES} = require('./rewriter'));

  // Import the helpers we need.
  ({count, starts, compact, repeat, invertLiterate, merge, attachCommentsToNode, locationDataToString, throwSyntaxError} = require('./helpers'));

  // The Lexer Class
  // ---------------

  // The Lexer class reads a stream of CoffeeScript and divvies it up into tagged
  // tokens. Some potential ambiguity in the grammar has been avoided by
  // pushing some extra smarts into the Lexer.
  exports.Lexer = Lexer = class Lexer {
    // **tokenize** is the Lexer's main method. Scan by attempting to match tokens
    // one at a time, using a regular expression anchored at the start of the
    // remaining code, or a custom recursive token-matching method
    // (for interpolations). When the next token has been recorded, we move forward
    // within the code past the token, and begin again.

    // Each tokenizing method is responsible for returning the number of characters
    // it has consumed.

    // Before returning the token stream, run it through the [Rewriter](rewriter.html).
    tokenize(code, opts = {}) {
      var consumed, end, i, ref;
      this.literate = opts.literate; // Are we lexing literate CoffeeScript?
      this.indent = 0; // The current indentation level.
      this.baseIndent = 0; // The overall minimum indentation level.
      this.indebt = 0; // The over-indentation at the current level.
      this.outdebt = 0; // The under-outdentation at the current level.
      this.indents = []; // The stack of all current indentation levels.
      this.indentLiteral = ''; // The indentation.
      this.ends = []; // The stack for pairing up tokens.
      this.tokens = []; // Stream of parsed tokens in the form `['TYPE', value, location data]`.
      this.seenFor = false; // Used to recognize `FORIN`, `FOROF` and `FORFROM` tokens.
      this.seenImport = false; // Used to recognize `IMPORT FROM? AS?` tokens.
      this.seenExport = false; // Used to recognize `EXPORT FROM? AS?` tokens.
      this.importSpecifierList = false; // Used to identify when in an `IMPORT {...} FROM? ...`.
      this.exportSpecifierList = false; // Used to identify when in an `EXPORT {...} FROM? ...`.
      this.csxDepth = 0; // Used to optimize CSX checks, how deep in CSX we are.
      this.csxObjAttribute = {}; // Used to detect if CSX attributes is wrapped in {} (<div {props...} />).
      this.chunkLine = opts.line || 0; // The start line for the current @chunk.
      this.chunkColumn = opts.column || 0; // The start column of the current @chunk.
      code = this.clean(code); // The stripped, cleaned original source code.
      
      // At every position, run through this list of attempted matches,
      // short-circuiting if any of them succeed. Their order determines precedence:
      // `@literalToken` is the fallback catch-all.
      i = 0;
      while (this.chunk = code.slice(i)) {
        consumed = this.identifierToken() || this.commentToken() || this.whitespaceToken() || this.lineToken() || this.stringToken() || this.numberToken() || this.csxToken() || this.regexToken() || this.jsToken() || this.literalToken();
        // Update position.
        [this.chunkLine, this.chunkColumn] = this.getLineAndColumnFromChunk(consumed);
        i += consumed;
        if (opts.untilBalanced && this.ends.length === 0) {
          return {
            tokens: this.tokens,
            index: i
          };
        }
      }
      this.closeIndentation();
      if (end = this.ends.pop()) {
        this.error(`missing ${end.tag}`, ((ref = end.origin) != null ? ref : end)[2]);
      }
      if (opts.rewrite === false) {
        return this.tokens;
      }
      return (new Rewriter).rewrite(this.tokens);
    }

    // Preprocess the code to remove leading and trailing whitespace, carriage
    // returns, etc. If we’re lexing literate CoffeeScript, strip external Markdown
    // by removing all lines that aren’t indented by at least four spaces or a tab.
    clean(code) {
      if (code.charCodeAt(0) === BOM) {
        code = code.slice(1);
      }
      code = code.replace(/\r/g, '').replace(TRAILING_SPACES, '');
      if (WHITESPACE.test(code)) {
        code = `\n${code}`;
        this.chunkLine--;
      }
      if (this.literate) {
        code = invertLiterate(code);
      }
      return code;
    }

    // Tokenizers
    // ----------

    // Matches identifying literals: variables, keywords, method names, etc.
    // Check to ensure that JavaScript reserved words aren’t being used as
    // identifiers. Because CoffeeScript reserves a handful of keywords that are
    // allowed in JavaScript, we’re careful not to tag them as keywords when
    // referenced as property names here, so you can still do `jQuery.is()` even
    // though `is` means `===` otherwise.
    identifierToken() {
      var alias, colon, colonOffset, colonToken, id, idLength, inCSXTag, input, match, poppedToken, prev, prevprev, ref, ref1, ref10, ref2, ref3, ref4, ref5, ref6, ref7, ref8, ref9, regExSuper, regex, sup, tag, tagToken;
      inCSXTag = this.atCSXTag();
      regex = inCSXTag ? CSX_ATTRIBUTE : IDENTIFIER;
      if (!(match = regex.exec(this.chunk))) {
        return 0;
      }
      [input, id, colon] = match;
      // Preserve length of id for location data
      idLength = id.length;
      poppedToken = void 0;
      if (id === 'own' && this.tag() === 'FOR') {
        this.token('OWN', id);
        return id.length;
      }
      if (id === 'from' && this.tag() === 'YIELD') {
        this.token('FROM', id);
        return id.length;
      }
      if (id === 'as' && this.seenImport) {
        if (this.value() === '*') {
          this.tokens[this.tokens.length - 1][0] = 'IMPORT_ALL';
        } else if (ref = this.value(true), indexOf.call(COFFEE_KEYWORDS, ref) >= 0) {
          prev = this.prev();
          [prev[0], prev[1]] = ['IDENTIFIER', this.value(true)];
        }
        if ((ref1 = this.tag()) === 'DEFAULT' || ref1 === 'IMPORT_ALL' || ref1 === 'IDENTIFIER') {
          this.token('AS', id);
          return id.length;
        }
      }
      if (id === 'as' && this.seenExport) {
        if ((ref2 = this.tag()) === 'IDENTIFIER' || ref2 === 'DEFAULT') {
          this.token('AS', id);
          return id.length;
        }
        if (ref3 = this.value(true), indexOf.call(COFFEE_KEYWORDS, ref3) >= 0) {
          prev = this.prev();
          [prev[0], prev[1]] = ['IDENTIFIER', this.value(true)];
          this.token('AS', id);
          return id.length;
        }
      }
      if (id === 'default' && this.seenExport && ((ref4 = this.tag()) === 'EXPORT' || ref4 === 'AS')) {
        this.token('DEFAULT', id);
        return id.length;
      }
      if (id === 'do' && (regExSuper = /^(\s*super)(?!\(\))/.exec(this.chunk.slice(3)))) {
        this.token('SUPER', 'super');
        this.token('CALL_START', '(');
        this.token('CALL_END', ')');
        [input, sup] = regExSuper;
        return sup.length + 3;
      }
      prev = this.prev();
      tag = colon || (prev != null) && (((ref5 = prev[0]) === '.' || ref5 === '?.' || ref5 === '::' || ref5 === '?::') || !prev.spaced && prev[0] === '@') ? 'PROPERTY' : 'IDENTIFIER';
      if (tag === 'IDENTIFIER' && (indexOf.call(JS_KEYWORDS, id) >= 0 || indexOf.call(COFFEE_KEYWORDS, id) >= 0) && !(this.exportSpecifierList && indexOf.call(COFFEE_KEYWORDS, id) >= 0)) {
        tag = id.toUpperCase();
        if (tag === 'WHEN' && (ref6 = this.tag(), indexOf.call(LINE_BREAK, ref6) >= 0)) {
          tag = 'LEADING_WHEN';
        } else if (tag === 'FOR') {
          this.seenFor = true;
        } else if (tag === 'UNLESS') {
          tag = 'IF';
        } else if (tag === 'IMPORT') {
          this.seenImport = true;
        } else if (tag === 'EXPORT') {
          this.seenExport = true;
        } else if (indexOf.call(UNARY, tag) >= 0) {
          tag = 'UNARY';
        } else if (indexOf.call(RELATION, tag) >= 0) {
          if (tag !== 'INSTANCEOF' && this.seenFor) {
            tag = 'FOR' + tag;
            this.seenFor = false;
          } else {
            tag = 'RELATION';
            if (this.value() === '!') {
              poppedToken = this.tokens.pop();
              id = '!' + id;
            }
          }
        }
      } else if (tag === 'IDENTIFIER' && this.seenFor && id === 'from' && isForFrom(prev)) {
        tag = 'FORFROM';
        this.seenFor = false;
      // Throw an error on attempts to use `get` or `set` as keywords, or
      // what CoffeeScript would normally interpret as calls to functions named
      // `get` or `set`, i.e. `get({foo: function () {}})`.
      } else if (tag === 'PROPERTY' && prev) {
        if (prev.spaced && (ref7 = prev[0], indexOf.call(CALLABLE, ref7) >= 0) && /^[gs]et$/.test(prev[1]) && this.tokens.length > 1 && ((ref8 = this.tokens[this.tokens.length - 2][0]) !== '.' && ref8 !== '?.' && ref8 !== '@')) {
          this.error(`'${prev[1]}' cannot be used as a keyword, or as a function call without parentheses`, prev[2]);
        } else if (prev[0] === '.' && this.tokens.length > 1 && (prevprev = this.tokens[this.tokens.length - 2])[0] === 'UNARY' && prevprev[1] === 'new') {
          prevprev[0] = 'IDENTIFIER';
        } else if (this.tokens.length > 2) {
          prevprev = this.tokens[this.tokens.length - 2];
          if (((ref9 = prev[0]) === '@' || ref9 === 'THIS') && prevprev && prevprev.spaced && /^[gs]et$/.test(prevprev[1]) && ((ref10 = this.tokens[this.tokens.length - 3][0]) !== '.' && ref10 !== '?.' && ref10 !== '@')) {
            this.error(`'${prevprev[1]}' cannot be used as a keyword, or as a function call without parentheses`, prevprev[2]);
          }
        }
      }
      if (tag === 'IDENTIFIER' && indexOf.call(RESERVED, id) >= 0) {
        this.error(`reserved word '${id}'`, {
          length: id.length
        });
      }
      if (!(tag === 'PROPERTY' || this.exportSpecifierList)) {
        if (indexOf.call(COFFEE_ALIASES, id) >= 0) {
          alias = id;
          id = COFFEE_ALIAS_MAP[id];
        }
        tag = (function() {
          switch (id) {
            case '!':
              return 'UNARY';
            case '==':
            case '!=':
              return 'COMPARE';
            case 'true':
            case 'false':
              return 'BOOL';
            case 'break':
            case 'continue':
            case 'debugger':
              return 'STATEMENT';
            case '&&':
            case '||':
              return id;
            default:
              return tag;
          }
        })();
      }
      tagToken = this.token(tag, id, 0, idLength);
      if (alias) {
        tagToken.origin = [tag, alias, tagToken[2]];
      }
      if (poppedToken) {
        [tagToken[2].first_line, tagToken[2].first_column] = [poppedToken[2].first_line, poppedToken[2].first_column];
      }
      if (colon) {
        colonOffset = input.lastIndexOf(inCSXTag ? '=' : ':');
        colonToken = this.token(':', ':', colonOffset, colon.length);
        if (inCSXTag) { // used by rewriter
          colonToken.csxColon = true;
        }
      }
      if (inCSXTag && tag === 'IDENTIFIER' && prev[0] !== ':') {
        this.token(',', ',', 0, 0, tagToken);
      }
      return input.length;
    }

    // Matches numbers, including decimals, hex, and exponential notation.
    // Be careful not to interfere with ranges in progress.
    numberToken() {
      var base, lexedLength, match, number, numberValue, tag;
      if (!(match = NUMBER.exec(this.chunk))) {
        return 0;
      }
      number = match[0];
      lexedLength = number.length;
      switch (false) {
        case !/^0[BOX]/.test(number):
          this.error(`radix prefix in '${number}' must be lowercase`, {
            offset: 1
          });
          break;
        case !/^(?!0x).*E/.test(number):
          this.error(`exponential notation in '${number}' must be indicated with a lowercase 'e'`, {
            offset: number.indexOf('E')
          });
          break;
        case !/^0\d*[89]/.test(number):
          this.error(`decimal literal '${number}' must not be prefixed with '0'`, {
            length: lexedLength
          });
          break;
        case !/^0\d+/.test(number):
          this.error(`octal literal '${number}' must be prefixed with '0o'`, {
            length: lexedLength
          });
      }
      base = (function() {
        switch (number.charAt(1)) {
          case 'b':
            return 2;
          case 'o':
            return 8;
          case 'x':
            return 16;
          default:
            return null;
        }
      })();
      numberValue = base != null ? parseInt(number.slice(2), base) : parseFloat(number);
      tag = numberValue === 2e308 ? 'INFINITY' : 'NUMBER';
      this.token(tag, number, 0, lexedLength);
      return lexedLength;
    }

    // Matches strings, including multiline strings, as well as heredocs, with or without
    // interpolation.
    stringToken() {
      var $, attempt, delimiter, doc, end, heredoc, i, indent, indentRegex, match, prev, quote, ref, regex, token, tokens;
      [quote] = STRING_START.exec(this.chunk) || [];
      if (!quote) {
        return 0;
      }
      // If the preceding token is `from` and this is an import or export statement,
      // properly tag the `from`.
      prev = this.prev();
      if (prev && this.value() === 'from' && (this.seenImport || this.seenExport)) {
        prev[0] = 'FROM';
      }
      regex = (function() {
        switch (quote) {
          case "'":
            return STRING_SINGLE;
          case '"':
            return STRING_DOUBLE;
          case "'''":
            return HEREDOC_SINGLE;
          case '"""':
            return HEREDOC_DOUBLE;
        }
      })();
      heredoc = quote.length === 3;
      ({
        tokens,
        index: end
      } = this.matchWithInterpolations(regex, quote));
      $ = tokens.length - 1;
      delimiter = quote.charAt(0);
      if (heredoc) {
        // Find the smallest indentation. It will be removed from all lines later.
        indent = null;
        doc = ((function() {
          var j, len, results;
          results = [];
          for (i = j = 0, len = tokens.length; j < len; i = ++j) {
            token = tokens[i];
            if (token[0] === 'NEOSTRING') {
              results.push(token[1]);
            }
          }
          return results;
        })()).join('#{}');
        while (match = HEREDOC_INDENT.exec(doc)) {
          attempt = match[1];
          if (indent === null || (0 < (ref = attempt.length) && ref < indent.length)) {
            indent = attempt;
          }
        }
        if (indent) {
          indentRegex = RegExp(`\\n${indent}`, "g");
        }
        this.mergeInterpolationTokens(tokens, {delimiter}, (value, i) => {
          value = this.formatString(value, {
            delimiter: quote
          });
          if (indentRegex) {
            value = value.replace(indentRegex, '\n');
          }
          if (i === 0) {
            value = value.replace(LEADING_BLANK_LINE, '');
          }
          if (i === $) {
            value = value.replace(TRAILING_BLANK_LINE, '');
          }
          return value;
        });
      } else {
        this.mergeInterpolationTokens(tokens, {delimiter}, (value, i) => {
          value = this.formatString(value, {
            delimiter: quote
          });
          // Remove indentation from multiline single-quoted strings.
          value = value.replace(SIMPLE_STRING_OMIT, function(match, offset) {
            if ((i === 0 && offset === 0) || (i === $ && offset + match.length === value.length)) {
              return '';
            } else {
              return ' ';
            }
          });
          return value;
        });
      }
      if (this.atCSXTag()) {
        this.token(',', ',', 0, 0, this.prev);
      }
      return end;
    }

    // Matches and consumes comments. The comments are taken out of the token
    // stream and saved for later, to be reinserted into the output after
    // everything has been parsed and the JavaScript code generated.
    commentToken(chunk = this.chunk) {
      var comment, commentAttachments, content, contents, here, i, match, matchIllegal, newLine, placeholderToken, prev;
      if (!(match = chunk.match(COMMENT))) {
        return 0;
      }
      [comment, here] = match;
      contents = null;
      // Does this comment follow code on the same line?
      newLine = /^\s*\n+\s*#/.test(comment);
      if (here) {
        matchIllegal = HERECOMMENT_ILLEGAL.exec(comment);
        if (matchIllegal) {
          this.error(`block comments cannot contain ${matchIllegal[0]}`, {
            offset: matchIllegal.index,
            length: matchIllegal[0].length
          });
        }
        // Parse indentation or outdentation as if this block comment didn’t exist.
        chunk = chunk.replace(`###${here}###`, '');
        // Remove leading newlines, like `Rewriter::removeLeadingNewlines`, to
        // avoid the creation of unwanted `TERMINATOR` tokens.
        chunk = chunk.replace(/^\n+/, '');
        this.lineToken(chunk);
        // Pull out the ###-style comment’s content, and format it.
        content = here;
        if (indexOf.call(content, '\n') >= 0) {
          content = content.replace(RegExp(`\\n${repeat(' ', this.indent)}`, "g"), '\n');
        }
        contents = [content];
      } else {
        // The `COMMENT` regex captures successive line comments as one token.
        // Remove any leading newlines before the first comment, but preserve
        // blank lines between line comments.
        content = comment.replace(/^(\n*)/, '');
        content = content.replace(/^([ |\t]*)#/gm, '');
        contents = content.split('\n');
      }
      commentAttachments = (function() {
        var j, len, results;
        results = [];
        for (i = j = 0, len = contents.length; j < len; i = ++j) {
          content = contents[i];
          results.push({
            content: content,
            here: here != null,
            newLine: newLine || i !== 0 // Line comments after the first one start new lines, by definition.
          });
        }
        return results;
      })();
      prev = this.prev();
      if (!prev) {
        // If there’s no previous token, create a placeholder token to attach
        // this comment to; and follow with a newline.
        commentAttachments[0].newLine = true;
        this.lineToken(this.chunk.slice(comment.length));
        placeholderToken = this.makeToken('JS', '');
        placeholderToken.generated = true;
        placeholderToken.comments = commentAttachments;
        this.tokens.push(placeholderToken);
        this.newlineToken(0);
      } else {
        attachCommentsToNode(commentAttachments, prev);
      }
      return comment.length;
    }

    // Matches JavaScript interpolated directly into the source via backticks.
    jsToken() {
      var match, script;
      if (!(this.chunk.charAt(0) === '`' && (match = HERE_JSTOKEN.exec(this.chunk) || JSTOKEN.exec(this.chunk)))) {
        return 0;
      }
      // Convert escaped backticks to backticks, and escaped backslashes
      // just before escaped backticks to backslashes
      script = match[1].replace(/\\+(`|$)/g, function(string) {
        // `string` is always a value like '\`', '\\\`', '\\\\\`', etc.
        // By reducing it to its latter half, we turn '\`' to '`', '\\\`' to '\`', etc.
        return string.slice(-Math.ceil(string.length / 2));
      });
      this.token('JS', script, 0, match[0].length);
      return match[0].length;
    }

    // Matches regular expression literals, as well as multiline extended ones.
    // Lexing regular expressions is difficult to distinguish from division, so we
    // borrow some basic heuristics from JavaScript and Ruby.
    regexToken() {
      var body, closed, comment, comments, end, flags, index, j, len, match, origin, prev, ref, ref1, regex, tokens;
      switch (false) {
        case !(match = REGEX_ILLEGAL.exec(this.chunk)):
          this.error(`regular expressions cannot begin with ${match[2]}`, {
            offset: match.index + match[1].length
          });
          break;
        case !(match = this.matchWithInterpolations(HEREGEX, '///')):
          ({tokens, index} = match);
          comments = this.chunk.slice(0, index).match(/\s+(#(?!{).*)/g);
          if (comments) {
            for (j = 0, len = comments.length; j < len; j++) {
              comment = comments[j];
              this.commentToken(comment);
            }
          }
          break;
        case !(match = REGEX.exec(this.chunk)):
          [regex, body, closed] = match;
          this.validateEscapes(body, {
            isRegex: true,
            offsetInChunk: 1
          });
          index = regex.length;
          prev = this.prev();
          if (prev) {
            if (prev.spaced && (ref = prev[0], indexOf.call(CALLABLE, ref) >= 0)) {
              if (!closed || POSSIBLY_DIVISION.test(regex)) {
                return 0;
              }
            } else if (ref1 = prev[0], indexOf.call(NOT_REGEX, ref1) >= 0) {
              return 0;
            }
          }
          if (!closed) {
            this.error('missing / (unclosed regex)');
          }
          break;
        default:
          return 0;
      }
      [flags] = REGEX_FLAGS.exec(this.chunk.slice(index));
      end = index + flags.length;
      origin = this.makeToken('REGEX', null, 0, end);
      switch (false) {
        case !!VALID_FLAGS.test(flags):
          this.error(`invalid regular expression flags ${flags}`, {
            offset: index,
            length: flags.length
          });
          break;
        case !(regex || tokens.length === 1):
          if (body) {
            body = this.formatRegex(body, {
              flags,
              delimiter: '/'
            });
          } else {
            body = this.formatHeregex(tokens[0][1], {flags});
          }
          this.token('REGEX', `${this.makeDelimitedLiteral(body, {
            delimiter: '/'
          })}${flags}`, 0, end, origin);
          break;
        default:
          this.token('REGEX_START', '(', 0, 0, origin);
          this.token('IDENTIFIER', 'RegExp', 0, 0);
          this.token('CALL_START', '(', 0, 0);
          this.mergeInterpolationTokens(tokens, {
            delimiter: '"',
            double: true
          }, (str) => {
            return this.formatHeregex(str, {flags});
          });
          if (flags) {
            this.token(',', ',', index - 1, 0);
            this.token('STRING', '"' + flags + '"', index - 1, flags.length);
          }
          this.token(')', ')', end - 1, 0);
          this.token('REGEX_END', ')', end - 1, 0);
      }
      return end;
    }

    // Matches newlines, indents, and outdents, and determines which is which.
    // If we can detect that the current line is continued onto the next line,
    // then the newline is suppressed:

    //     elements
    //       .each( ... )
    //       .map( ... )

    // Keeps track of the level of indentation, because a single outdent token
    // can close multiple indents, so we need to know how far in we happen to be.
    lineToken(chunk = this.chunk) {
      var backslash, diff, indent, match, minLiteralLength, newIndentLiteral, noNewlines, prev, size;
      if (!(match = MULTI_DENT.exec(chunk))) {
        return 0;
      }
      indent = match[0];
      prev = this.prev();
      backslash = (prev != null ? prev[0] : void 0) === '\\';
      if (!(backslash && this.seenFor)) {
        this.seenFor = false;
      }
      if (!((backslash && this.seenImport) || this.importSpecifierList)) {
        this.seenImport = false;
      }
      if (!((backslash && this.seenExport) || this.exportSpecifierList)) {
        this.seenExport = false;
      }
      size = indent.length - 1 - indent.lastIndexOf('\n');
      noNewlines = this.unfinished();
      newIndentLiteral = size > 0 ? indent.slice(-size) : '';
      if (!/^(.?)\1*$/.exec(newIndentLiteral)) {
        this.error('mixed indentation', {
          offset: indent.length
        });
        return indent.length;
      }
      minLiteralLength = Math.min(newIndentLiteral.length, this.indentLiteral.length);
      if (newIndentLiteral.slice(0, minLiteralLength) !== this.indentLiteral.slice(0, minLiteralLength)) {
        this.error('indentation mismatch', {
          offset: indent.length
        });
        return indent.length;
      }
      if (size - this.indebt === this.indent) {
        if (noNewlines) {
          this.suppressNewlines();
        } else {
          this.newlineToken(0);
        }
        return indent.length;
      }
      if (size > this.indent) {
        if (noNewlines) {
          if (!backslash) {
            this.indebt = size - this.indent;
          }
          this.suppressNewlines();
          return indent.length;
        }
        if (!this.tokens.length) {
          this.baseIndent = this.indent = size;
          this.indentLiteral = newIndentLiteral;
          return indent.length;
        }
        diff = size - this.indent + this.outdebt;
        this.token('INDENT', diff, indent.length - size, size);
        this.indents.push(diff);
        this.ends.push({
          tag: 'OUTDENT'
        });
        this.outdebt = this.indebt = 0;
        this.indent = size;
        this.indentLiteral = newIndentLiteral;
      } else if (size < this.baseIndent) {
        this.error('missing indentation', {
          offset: indent.length
        });
      } else {
        this.indebt = 0;
        this.outdentToken(this.indent - size, noNewlines, indent.length);
      }
      return indent.length;
    }

    // Record an outdent token or multiple tokens, if we happen to be moving back
    // inwards past several recorded indents. Sets new @indent value.
    outdentToken(moveOut, noNewlines, outdentLength) {
      var decreasedIndent, dent, lastIndent, ref;
      decreasedIndent = this.indent - moveOut;
      while (moveOut > 0) {
        lastIndent = this.indents[this.indents.length - 1];
        if (!lastIndent) {
          this.outdebt = moveOut = 0;
        } else if (this.outdebt && moveOut <= this.outdebt) {
          this.outdebt -= moveOut;
          moveOut = 0;
        } else {
          dent = this.indents.pop() + this.outdebt;
          if (outdentLength && (ref = this.chunk[outdentLength], indexOf.call(INDENTABLE_CLOSERS, ref) >= 0)) {
            decreasedIndent -= dent - moveOut;
            moveOut = dent;
          }
          this.outdebt = 0;
          // pair might call outdentToken, so preserve decreasedIndent
          this.pair('OUTDENT');
          this.token('OUTDENT', moveOut, 0, outdentLength);
          moveOut -= dent;
        }
      }
      if (dent) {
        this.outdebt -= moveOut;
      }
      this.suppressSemicolons();
      if (!(this.tag() === 'TERMINATOR' || noNewlines)) {
        this.token('TERMINATOR', '\n', outdentLength, 0);
      }
      this.indent = decreasedIndent;
      this.indentLiteral = this.indentLiteral.slice(0, decreasedIndent);
      return this;
    }

    // Matches and consumes non-meaningful whitespace. Tag the previous token
    // as being “spaced”, because there are some cases where it makes a difference.
    whitespaceToken() {
      var match, nline, prev;
      if (!((match = WHITESPACE.exec(this.chunk)) || (nline = this.chunk.charAt(0) === '\n'))) {
        return 0;
      }
      prev = this.prev();
      if (prev) {
        prev[match ? 'spaced' : 'newLine'] = true;
      }
      if (match) {
        return match[0].length;
      } else {
        return 0;
      }
    }

    // Generate a newline token. Consecutive newlines get merged together.
    newlineToken(offset) {
      this.suppressSemicolons();
      if (this.tag() !== 'TERMINATOR') {
        this.token('TERMINATOR', '\n', offset, 0);
      }
      return this;
    }

    // Use a `\` at a line-ending to suppress the newline.
    // The slash is removed here once its job is done.
    suppressNewlines() {
      var prev;
      prev = this.prev();
      if (prev[1] === '\\') {
        if (prev.comments && this.tokens.length > 1) {
          // `@tokens.length` should be at least 2 (some code, then `\`).
          // If something puts a `\` after nothing, they deserve to lose any
          // comments that trail it.
          attachCommentsToNode(prev.comments, this.tokens[this.tokens.length - 2]);
        }
        this.tokens.pop();
      }
      return this;
    }

    // CSX is like JSX but for CoffeeScript.
    csxToken() {
      var afterTag, colon, csxTag, end, firstChar, id, input, match, origin, prev, prevChar, ref, token, tokens;
      firstChar = this.chunk[0];
      // Check the previous token to detect if attribute is spread.
      prevChar = this.tokens.length > 0 ? this.tokens[this.tokens.length - 1][0] : '';
      if (firstChar === '<') {
        match = CSX_IDENTIFIER.exec(this.chunk.slice(1)) || CSX_FRAGMENT_IDENTIFIER.exec(this.chunk.slice(1));
        // Not the right hand side of an unspaced comparison (i.e. `a<b`).
        if (!(match && (this.csxDepth > 0 || !(prev = this.prev()) || prev.spaced || (ref = prev[0], indexOf.call(COMPARABLE_LEFT_SIDE, ref) < 0)))) {
          return 0;
        }
        [input, id, colon] = match;
        origin = this.token('CSX_TAG', id, 1, id.length);
        this.token('CALL_START', '(');
        this.token('[', '[');
        this.ends.push({
          tag: '/>',
          origin: origin,
          name: id
        });
        this.csxDepth++;
        return id.length + 1;
      } else if (csxTag = this.atCSXTag()) {
        if (this.chunk.slice(0, 2) === '/>') {
          this.pair('/>');
          this.token(']', ']', 0, 2);
          this.token('CALL_END', ')', 0, 2);
          this.csxDepth--;
          return 2;
        } else if (firstChar === '{') {
          if (prevChar === ':') {
            token = this.token('(', '(');
            this.csxObjAttribute[this.csxDepth] = false;
          } else {
            token = this.token('{', '{');
            this.csxObjAttribute[this.csxDepth] = true;
          }
          this.ends.push({
            tag: '}',
            origin: token
          });
          return 1;
        } else if (firstChar === '>') {
          // Ignore terminators inside a tag.
          this.pair('/>'); // As if the current tag was self-closing.
          origin = this.token(']', ']');
          this.token(',', ',');
          ({
            tokens,
            index: end
          } = this.matchWithInterpolations(INSIDE_CSX, '>', '</', CSX_INTERPOLATION));
          this.mergeInterpolationTokens(tokens, {
            delimiter: '"'
          }, (value, i) => {
            return this.formatString(value, {
              delimiter: '>'
            });
          });
          match = CSX_IDENTIFIER.exec(this.chunk.slice(end)) || CSX_FRAGMENT_IDENTIFIER.exec(this.chunk.slice(end));
          if (!match || match[1] !== csxTag.name) {
            this.error(`expected corresponding CSX closing tag for ${csxTag.name}`, csxTag.origin[2]);
          }
          afterTag = end + csxTag.name.length;
          if (this.chunk[afterTag] !== '>') {
            this.error("missing closing > after tag name", {
              offset: afterTag,
              length: 1
            });
          }
          // +1 for the closing `>`.
          this.token('CALL_END', ')', end, csxTag.name.length + 1);
          this.csxDepth--;
          return afterTag + 1;
        } else {
          return 0;
        }
      } else if (this.atCSXTag(1)) {
        if (firstChar === '}') {
          this.pair(firstChar);
          if (this.csxObjAttribute[this.csxDepth]) {
            this.token('}', '}');
            this.csxObjAttribute[this.csxDepth] = false;
          } else {
            this.token(')', ')');
          }
          this.token(',', ',');
          return 1;
        } else {
          return 0;
        }
      } else {
        return 0;
      }
    }

    atCSXTag(depth = 0) {
      var i, last, ref;
      if (this.csxDepth === 0) {
        return false;
      }
      i = this.ends.length - 1;
      while (((ref = this.ends[i]) != null ? ref.tag : void 0) === 'OUTDENT' || depth-- > 0) { // Ignore indents.
        i--;
      }
      last = this.ends[i];
      return (last != null ? last.tag : void 0) === '/>' && last;
    }

    // We treat all other single characters as a token. E.g.: `( ) , . !`
    // Multi-character operators are also literal tokens, so that Jison can assign
    // the proper order of operations. There are some symbols that we tag specially
    // here. `;` and newlines are both treated as a `TERMINATOR`, we distinguish
    // parentheses that indicate a method call from regular parentheses, and so on.
    literalToken() {
      var match, message, origin, prev, ref, ref1, ref2, ref3, ref4, skipToken, tag, token, value;
      if (match = OPERATOR.exec(this.chunk)) {
        [value] = match;
        if (CODE.test(value)) {
          this.tagParameters();
        }
      } else {
        value = this.chunk.charAt(0);
      }
      tag = value;
      prev = this.prev();
      if (prev && indexOf.call(['=', ...COMPOUND_ASSIGN], value) >= 0) {
        skipToken = false;
        if (value === '=' && ((ref = prev[1]) === '||' || ref === '&&') && !prev.spaced) {
          prev[0] = 'COMPOUND_ASSIGN';
          prev[1] += '=';
          prev = this.tokens[this.tokens.length - 2];
          skipToken = true;
        }
        if (prev && prev[0] !== 'PROPERTY') {
          origin = (ref1 = prev.origin) != null ? ref1 : prev;
          message = isUnassignable(prev[1], origin[1]);
          if (message) {
            this.error(message, origin[2]);
          }
        }
        if (skipToken) {
          return value.length;
        }
      }
      if (value === '{' && this.seenImport) {
        this.importSpecifierList = true;
      } else if (this.importSpecifierList && value === '}') {
        this.importSpecifierList = false;
      } else if (value === '{' && (prev != null ? prev[0] : void 0) === 'EXPORT') {
        this.exportSpecifierList = true;
      } else if (this.exportSpecifierList && value === '}') {
        this.exportSpecifierList = false;
      }
      if (value === ';') {
        if (ref2 = prev != null ? prev[0] : void 0, indexOf.call(['=', ...UNFINISHED], ref2) >= 0) {
          this.error('unexpected ;');
        }
        this.seenFor = this.seenImport = this.seenExport = false;
        tag = 'TERMINATOR';
      } else if (value === '*' && (prev != null ? prev[0] : void 0) === 'EXPORT') {
        tag = 'EXPORT_ALL';
      } else if (indexOf.call(MATH, value) >= 0) {
        tag = 'MATH';
      } else if (indexOf.call(COMPARE, value) >= 0) {
        tag = 'COMPARE';
      } else if (indexOf.call(COMPOUND_ASSIGN, value) >= 0) {
        tag = 'COMPOUND_ASSIGN';
      } else if (indexOf.call(UNARY, value) >= 0) {
        tag = 'UNARY';
      } else if (indexOf.call(UNARY_MATH, value) >= 0) {
        tag = 'UNARY_MATH';
      } else if (indexOf.call(SHIFT, value) >= 0) {
        tag = 'SHIFT';
      } else if (value === '?' && (prev != null ? prev.spaced : void 0)) {
        tag = 'BIN?';
      } else if (prev) {
        if (value === '(' && !prev.spaced && (ref3 = prev[0], indexOf.call(CALLABLE, ref3) >= 0)) {
          if (prev[0] === '?') {
            prev[0] = 'FUNC_EXIST';
          }
          tag = 'CALL_START';
        } else if (value === '[' && (((ref4 = prev[0], indexOf.call(INDEXABLE, ref4) >= 0) && !prev.spaced) || (prev[0] === '::'))) { // `.prototype` can’t be a method you can call.
          tag = 'INDEX_START';
          switch (prev[0]) {
            case '?':
              prev[0] = 'INDEX_SOAK';
          }
        }
      }
      token = this.makeToken(tag, value);
      switch (value) {
        case '(':
        case '{':
        case '[':
          this.ends.push({
            tag: INVERSES[value],
            origin: token
          });
          break;
        case ')':
        case '}':
        case ']':
          this.pair(value);
      }
      this.tokens.push(this.makeToken(tag, value));
      return value.length;
    }

    // Token Manipulators
    // ------------------

    // A source of ambiguity in our grammar used to be parameter lists in function
    // definitions versus argument lists in function calls. Walk backwards, tagging
    // parameters specially in order to make things easier for the parser.
    tagParameters() {
      var i, paramEndToken, stack, tok, tokens;
      if (this.tag() !== ')') {
        return this;
      }
      stack = [];
      ({tokens} = this);
      i = tokens.length;
      paramEndToken = tokens[--i];
      paramEndToken[0] = 'PARAM_END';
      while (tok = tokens[--i]) {
        switch (tok[0]) {
          case ')':
            stack.push(tok);
            break;
          case '(':
          case 'CALL_START':
            if (stack.length) {
              stack.pop();
            } else if (tok[0] === '(') {
              tok[0] = 'PARAM_START';
              return this;
            } else {
              paramEndToken[0] = 'CALL_END';
              return this;
            }
        }
      }
      return this;
    }

    // Close up all remaining open blocks at the end of the file.
    closeIndentation() {
      return this.outdentToken(this.indent);
    }

    // Match the contents of a delimited token and expand variables and expressions
    // inside it using Ruby-like notation for substitution of arbitrary
    // expressions.

    //     "Hello #{name.capitalize()}."

    // If it encounters an interpolation, this method will recursively create a new
    // Lexer and tokenize until the `{` of `#{` is balanced with a `}`.

    //  - `regex` matches the contents of a token (but not `delimiter`, and not
    //    `#{` if interpolations are desired).
    //  - `delimiter` is the delimiter of the token. Examples are `'`, `"`, `'''`,
    //    `"""` and `///`.
    //  - `closingDelimiter` is different from `delimiter` only in CSX
    //  - `interpolators` matches the start of an interpolation, for CSX it's both
    //    `{` and `<` (i.e. nested CSX tag)

    // This method allows us to have strings within interpolations within strings,
    // ad infinitum.
    matchWithInterpolations(regex, delimiter, closingDelimiter, interpolators) {
      var braceInterpolator, close, column, firstToken, index, interpolationOffset, interpolator, lastToken, line, match, nested, offsetInChunk, open, ref, ref1, rest, str, strPart, tokens;
      if (closingDelimiter == null) {
        closingDelimiter = delimiter;
      }
      if (interpolators == null) {
        interpolators = /^#\{/;
      }
      tokens = [];
      offsetInChunk = delimiter.length;
      if (this.chunk.slice(0, offsetInChunk) !== delimiter) {
        return null;
      }
      str = this.chunk.slice(offsetInChunk);
      while (true) {
        [strPart] = regex.exec(str);
        this.validateEscapes(strPart, {
          isRegex: delimiter.charAt(0) === '/',
          offsetInChunk
        });
        // Push a fake `'NEOSTRING'` token, which will get turned into a real string later.
        tokens.push(this.makeToken('NEOSTRING', strPart, offsetInChunk));
        str = str.slice(strPart.length);
        offsetInChunk += strPart.length;
        if (!(match = interpolators.exec(str))) {
          break;
        }
        [interpolator] = match;
        // To remove the `#` in `#{`.
        interpolationOffset = interpolator.length - 1;
        [line, column] = this.getLineAndColumnFromChunk(offsetInChunk + interpolationOffset);
        rest = str.slice(interpolationOffset);
        ({
          tokens: nested,
          index
        } = new Lexer().tokenize(rest, {
          line: line,
          column: column,
          untilBalanced: true
        }));
        // Account for the `#` in `#{`.
        index += interpolationOffset;
        braceInterpolator = str[index - 1] === '}';
        if (braceInterpolator) {
          // Turn the leading and trailing `{` and `}` into parentheses. Unnecessary
          // parentheses will be removed later.
          [open] = nested, [close] = slice.call(nested, -1);
          open[0] = open[1] = '(';
          close[0] = close[1] = ')';
          close.origin = ['', 'end of interpolation', close[2]];
        }
        if (((ref = nested[1]) != null ? ref[0] : void 0) === 'TERMINATOR') {
          // Remove leading `'TERMINATOR'` (if any).
          nested.splice(1, 1);
        }
        if (((ref1 = nested[nested.length - 3]) != null ? ref1[0] : void 0) === 'INDENT' && nested[nested.length - 2][0] === 'OUTDENT') {
          // Remove trailing `'INDENT'/'OUTDENT'` pair (if any).
          nested.splice(-3, 2);
        }
        if (!braceInterpolator) {
          // We are not using `{` and `}`, so wrap the interpolated tokens instead.
          open = this.makeToken('(', '(', offsetInChunk, 0);
          close = this.makeToken(')', ')', offsetInChunk + index, 0);
          nested = [open, ...nested, close];
        }
        // Push a fake `'TOKENS'` token, which will get turned into real tokens later.
        tokens.push(['TOKENS', nested]);
        str = str.slice(index);
        offsetInChunk += index;
      }
      if (str.slice(0, closingDelimiter.length) !== closingDelimiter) {
        this.error(`missing ${closingDelimiter}`, {
          length: delimiter.length
        });
      }
      [firstToken] = tokens, [lastToken] = slice.call(tokens, -1);
      firstToken[2].first_column -= delimiter.length;
      if (lastToken[1].substr(-1) === '\n') {
        lastToken[2].last_line += 1;
        lastToken[2].last_column = closingDelimiter.length - 1;
      } else {
        lastToken[2].last_column += closingDelimiter.length;
      }
      if (lastToken[1].length === 0) {
        lastToken[2].last_column -= 1;
      }
      return {
        tokens,
        index: offsetInChunk + closingDelimiter.length
      };
    }

    // Merge the array `tokens` of the fake token types `'TOKENS'` and `'NEOSTRING'`
    // (as returned by `matchWithInterpolations`) into the token stream. The value
    // of `'NEOSTRING'`s are converted using `fn` and turned into strings using
    // `options` first.
    mergeInterpolationTokens(tokens, options, fn) {
      var converted, firstEmptyStringIndex, firstIndex, i, j, k, lastToken, len, len1, locationToken, lparen, placeholderToken, plusToken, rparen, tag, token, tokensToPush, val, value;
      if (tokens.length > 1) {
        lparen = this.token('STRING_START', '(', 0, 0);
      }
      firstIndex = this.tokens.length;
      for (i = j = 0, len = tokens.length; j < len; i = ++j) {
        token = tokens[i];
        [tag, value] = token;
        switch (tag) {
          case 'TOKENS':
            if (value.length === 2) {
              if (!(value[0].comments || value[1].comments)) {
                // Optimize out empty interpolations (an empty pair of parentheses).
                continue;
              }
              // There are comments (and nothing else) in this interpolation.
              if (this.csxDepth === 0) {
                // This is an interpolated string, not a CSX tag; and for whatever
                // reason `` `a${/*test*/}b` `` is invalid JS. So compile to
                // `` `a${/*test*/''}b` `` instead.
                placeholderToken = this.makeToken('STRING', "''");
              } else {
                placeholderToken = this.makeToken('JS', '');
              }
              // Use the same location data as the first parenthesis.
              placeholderToken[2] = value[0][2];
              for (k = 0, len1 = value.length; k < len1; k++) {
                val = value[k];
                if (!val.comments) {
                  continue;
                }
                if (placeholderToken.comments == null) {
                  placeholderToken.comments = [];
                }
                placeholderToken.comments.push(...val.comments);
              }
              value.splice(1, 0, placeholderToken);
            }
            // Push all the tokens in the fake `'TOKENS'` token. These already have
            // sane location data.
            locationToken = value[0];
            tokensToPush = value;
            break;
          case 'NEOSTRING':
            // Convert `'NEOSTRING'` into `'STRING'`.
            converted = fn.call(this, token[1], i);
            // Optimize out empty strings. We ensure that the tokens stream always
            // starts with a string token, though, to make sure that the result
            // really is a string.
            if (converted.length === 0) {
              if (i === 0) {
                firstEmptyStringIndex = this.tokens.length;
              } else {
                continue;
              }
            }
            // However, there is one case where we can optimize away a starting
            // empty string.
            if (i === 2 && (firstEmptyStringIndex != null)) {
              this.tokens.splice(firstEmptyStringIndex, 2); // Remove empty string and the plus.
            }
            token[0] = 'STRING';
            token[1] = this.makeDelimitedLiteral(converted, options);
            locationToken = token;
            tokensToPush = [token];
        }
        if (this.tokens.length > firstIndex) {
          // Create a 0-length `+` token.
          plusToken = this.token('+', '+');
          plusToken[2] = {
            first_line: locationToken[2].first_line,
            first_column: locationToken[2].first_column,
            last_line: locationToken[2].first_line,
            last_column: locationToken[2].first_column
          };
        }
        this.tokens.push(...tokensToPush);
      }
      if (lparen) {
        [lastToken] = slice.call(tokens, -1);
        lparen.origin = [
          'STRING',
          null,
          {
            first_line: lparen[2].first_line,
            first_column: lparen[2].first_column,
            last_line: lastToken[2].last_line,
            last_column: lastToken[2].last_column
          }
        ];
        lparen[2] = lparen.origin[2];
        rparen = this.token('STRING_END', ')');
        return rparen[2] = {
          first_line: lastToken[2].last_line,
          first_column: lastToken[2].last_column,
          last_line: lastToken[2].last_line,
          last_column: lastToken[2].last_column
        };
      }
    }

    // Pairs up a closing token, ensuring that all listed pairs of tokens are
    // correctly balanced throughout the course of the token stream.
    pair(tag) {
      var lastIndent, prev, ref, ref1, wanted;
      ref = this.ends, [prev] = slice.call(ref, -1);
      if (tag !== (wanted = prev != null ? prev.tag : void 0)) {
        if ('OUTDENT' !== wanted) {
          this.error(`unmatched ${tag}`);
        }
        // Auto-close `INDENT` to support syntax like this:

        //     el.click((event) ->
        //       el.hide())

        ref1 = this.indents, [lastIndent] = slice.call(ref1, -1);
        this.outdentToken(lastIndent, true);
        return this.pair(tag);
      }
      return this.ends.pop();
    }

    // Helpers
    // -------

    // Returns the line and column number from an offset into the current chunk.

    // `offset` is a number of characters into `@chunk`.
    getLineAndColumnFromChunk(offset) {
      var column, lastLine, lineCount, ref, string;
      if (offset === 0) {
        return [this.chunkLine, this.chunkColumn];
      }
      if (offset >= this.chunk.length) {
        string = this.chunk;
      } else {
        string = this.chunk.slice(0, +(offset - 1) + 1 || 9e9);
      }
      lineCount = count(string, '\n');
      column = this.chunkColumn;
      if (lineCount > 0) {
        ref = string.split('\n'), [lastLine] = slice.call(ref, -1);
        column = lastLine.length;
      } else {
        column += string.length;
      }
      return [this.chunkLine + lineCount, column];
    }

    // Same as `token`, except this just returns the token without adding it
    // to the results.
    makeToken(tag, value, offsetInChunk = 0, length = value.length, origin) {
      var lastCharacter, locationData, token;
      locationData = {};
      [locationData.first_line, locationData.first_column] = this.getLineAndColumnFromChunk(offsetInChunk);
      // Use length - 1 for the final offset - we’re supplying the last_line and the last_column,
      // so if last_column == first_column, then we’re looking at a character of length 1.
      lastCharacter = length > 0 ? length - 1 : 0;
      [locationData.last_line, locationData.last_column] = this.getLineAndColumnFromChunk(offsetInChunk + lastCharacter);
      token = [tag, value, locationData];
      if (origin) {
        token.origin = origin;
      }
      return token;
    }

    // Add a token to the results.
    // `offset` is the offset into the current `@chunk` where the token starts.
    // `length` is the length of the token in the `@chunk`, after the offset.  If
    // not specified, the length of `value` will be used.

    // Returns the new token.
    token(tag, value, offsetInChunk, length, origin) {
      var token;
      token = this.makeToken(tag, value, offsetInChunk, length, origin);
      this.tokens.push(token);
      return token;
    }

    // Peek at the last tag in the token stream.
    tag() {
      var ref, token;
      ref = this.tokens, [token] = slice.call(ref, -1);
      return token != null ? token[0] : void 0;
    }

    // Peek at the last value in the token stream.
    value(useOrigin = false) {
      var ref, ref1, token;
      ref = this.tokens, [token] = slice.call(ref, -1);
      if (useOrigin && ((token != null ? token.origin : void 0) != null)) {
        return (ref1 = token.origin) != null ? ref1[1] : void 0;
      } else {
        return token != null ? token[1] : void 0;
      }
    }

    // Get the previous token in the token stream.
    prev() {
      return this.tokens[this.tokens.length - 1];
    }

    // Are we in the midst of an unfinished expression?
    unfinished() {
      var ref;
      return LINE_CONTINUER.test(this.chunk) || (ref = this.tag(), indexOf.call(UNFINISHED, ref) >= 0);
    }

    formatString(str, options) {
      return this.replaceUnicodeCodePointEscapes(str.replace(STRING_OMIT, '$1'), options);
    }

    formatHeregex(str, options) {
      return this.formatRegex(str.replace(HEREGEX_OMIT, '$1$2'), merge(options, {
        delimiter: '///'
      }));
    }

    formatRegex(str, options) {
      return this.replaceUnicodeCodePointEscapes(str, options);
    }

    unicodeCodePointToUnicodeEscapes(codePoint) {
      var high, low, toUnicodeEscape;
      toUnicodeEscape = function(val) {
        var str;
        str = val.toString(16);
        return `\\u${repeat('0', 4 - str.length)}${str}`;
      };
      if (codePoint < 0x10000) {
        return toUnicodeEscape(codePoint);
      }
      // surrogate pair
      high = Math.floor((codePoint - 0x10000) / 0x400) + 0xD800;
      low = (codePoint - 0x10000) % 0x400 + 0xDC00;
      return `${toUnicodeEscape(high)}${toUnicodeEscape(low)}`;
    }

    // Replace `\u{...}` with `\uxxxx[\uxxxx]` in regexes without `u` flag
    replaceUnicodeCodePointEscapes(str, options) {
      var shouldReplace;
      shouldReplace = (options.flags != null) && indexOf.call(options.flags, 'u') < 0;
      return str.replace(UNICODE_CODE_POINT_ESCAPE, (match, escapedBackslash, codePointHex, offset) => {
        var codePointDecimal;
        if (escapedBackslash) {
          return escapedBackslash;
        }
        codePointDecimal = parseInt(codePointHex, 16);
        if (codePointDecimal > 0x10ffff) {
          this.error("unicode code point escapes greater than \\u{10ffff} are not allowed", {
            offset: offset + options.delimiter.length,
            length: codePointHex.length + 4
          });
        }
        if (!shouldReplace) {
          return match;
        }
        return this.unicodeCodePointToUnicodeEscapes(codePointDecimal);
      });
    }

    // Validates escapes in strings and regexes.
    validateEscapes(str, options = {}) {
      var before, hex, invalidEscape, invalidEscapeRegex, match, message, octal, ref, unicode, unicodeCodePoint;
      invalidEscapeRegex = options.isRegex ? REGEX_INVALID_ESCAPE : STRING_INVALID_ESCAPE;
      match = invalidEscapeRegex.exec(str);
      if (!match) {
        return;
      }
      match[0], before = match[1], octal = match[2], hex = match[3], unicodeCodePoint = match[4], unicode = match[5];
      message = octal ? "octal escape sequences are not allowed" : "invalid escape sequence";
      invalidEscape = `\\${octal || hex || unicodeCodePoint || unicode}`;
      return this.error(`${message} ${invalidEscape}`, {
        offset: ((ref = options.offsetInChunk) != null ? ref : 0) + match.index + before.length,
        length: invalidEscape.length
      });
    }

    // Constructs a string or regex by escaping certain characters.
    makeDelimitedLiteral(body, options = {}) {
      var regex;
      if (body === '' && options.delimiter === '/') {
        body = '(?:)';
      }
      regex = RegExp(`(\\\\\\\\)|(\\\\0(?=[1-7]))|\\\\?(${options.delimiter // Escaped backslash.
      // Null character mistaken as octal escape.
      // (Possibly escaped) delimiter.
      // (Possibly escaped) newlines.
      // Other escapes.
})|\\\\?(?:(\\n)|(\\r)|(\\u2028)|(\\u2029))|(\\\\.)`, "g");
      body = body.replace(regex, function(match, backslash, nul, delimiter, lf, cr, ls, ps, other) {
        switch (false) {
          // Ignore escaped backslashes.
          case !backslash:
            if (options.double) {
              return backslash + backslash;
            } else {
              return backslash;
            }
          case !nul:
            return '\\x00';
          case !delimiter:
            return `\\${delimiter}`;
          case !lf:
            return '\\n';
          case !cr:
            return '\\r';
          case !ls:
            return '\\u2028';
          case !ps:
            return '\\u2029';
          case !other:
            if (options.double) {
              return `\\${other}`;
            } else {
              return other;
            }
        }
      });
      return `${options.delimiter}${body}${options.delimiter}`;
    }

    suppressSemicolons() {
      var ref, ref1, results;
      results = [];
      while (this.value() === ';') {
        this.tokens.pop();
        if (ref = (ref1 = this.prev()) != null ? ref1[0] : void 0, indexOf.call(['=', ...UNFINISHED], ref) >= 0) {
          results.push(this.error('unexpected ;'));
        } else {
          results.push(void 0);
        }
      }
      return results;
    }

    // Throws an error at either a given offset from the current chunk or at the
    // location of a token (`token[2]`).
    error(message, options = {}) {
      var first_column, first_line, location, ref, ref1;
      location = 'first_line' in options ? options : ([first_line, first_column] = this.getLineAndColumnFromChunk((ref = options.offset) != null ? ref : 0), {
        first_line,
        first_column,
        last_column: first_column + ((ref1 = options.length) != null ? ref1 : 1) - 1
      });
      return throwSyntaxError(message, location);
    }

  };

  // Helper functions
  // ----------------
  isUnassignable = function(name, displayName = name) {
    switch (false) {
      case indexOf.call([...JS_KEYWORDS, ...COFFEE_KEYWORDS], name) < 0:
        return `keyword '${displayName}' can't be assigned`;
      case indexOf.call(STRICT_PROSCRIBED, name) < 0:
        return `'${displayName}' can't be assigned`;
      case indexOf.call(RESERVED, name) < 0:
        return `reserved word '${displayName}' can't be assigned`;
      default:
        return false;
    }
  };

  exports.isUnassignable = isUnassignable;

  // `from` isn’t a CoffeeScript keyword, but it behaves like one in `import` and
  // `export` statements (handled above) and in the declaration line of a `for`
  // loop. Try to detect when `from` is a variable identifier and when it is this
  // “sometimes” keyword.
  isForFrom = function(prev) {
    var ref;
    if (prev[0] === 'IDENTIFIER') {
      // `for i from from`, `for from from iterable`
      if (prev[1] === 'from') {
        prev[1][0] = 'IDENTIFIER';
        true;
      }
      // `for i from iterable`
      return true;
    // `for from…`
    } else if (prev[0] === 'FOR') {
      return false;
    // `for {from}…`, `for [from]…`, `for {a, from}…`, `for {a: from}…`
    } else if ((ref = prev[1]) === '{' || ref === '[' || ref === ',' || ref === ':') {
      return false;
    } else {
      return true;
    }
  };

  // Constants
  // ---------

  // Keywords that CoffeeScript shares in common with JavaScript.
  JS_KEYWORDS = ['true', 'false', 'null', 'this', 'new', 'delete', 'typeof', 'in', 'instanceof', 'return', 'throw', 'break', 'continue', 'debugger', 'yield', 'await', 'if', 'else', 'switch', 'for', 'while', 'do', 'try', 'catch', 'finally', 'class', 'extends', 'super', 'import', 'export', 'default'];

  // CoffeeScript-only keywords.
  COFFEE_KEYWORDS = ['undefined', 'Infinity', 'NaN', 'then', 'unless', 'until', 'loop', 'of', 'by', 'when'];

  COFFEE_ALIAS_MAP = {
    and: '&&',
    or: '||',
    is: '==',
    isnt: '!=',
    not: '!',
    yes: 'true',
    no: 'false',
    on: 'true',
    off: 'false'
  };

  COFFEE_ALIASES = (function() {
    var results;
    results = [];
    for (key in COFFEE_ALIAS_MAP) {
      results.push(key);
    }
    return results;
  })();

  COFFEE_KEYWORDS = COFFEE_KEYWORDS.concat(COFFEE_ALIASES);

  // The list of keywords that are reserved by JavaScript, but not used, or are
  // used by CoffeeScript internally. We throw an error when these are encountered,
  // to avoid having a JavaScript error at runtime.
  RESERVED = ['case', 'function', 'var', 'void', 'with', 'const', 'let', 'enum', 'native', 'implements', 'interface', 'package', 'private', 'protected', 'public', 'static'];

  STRICT_PROSCRIBED = ['arguments', 'eval'];

  // The superset of both JavaScript keywords and reserved words, none of which may
  // be used as identifiers or properties.
  exports.JS_FORBIDDEN = JS_KEYWORDS.concat(RESERVED).concat(STRICT_PROSCRIBED);

  // The character code of the nasty Microsoft madness otherwise known as the BOM.
  BOM = 65279;

  // Token matching regexes.
  IDENTIFIER = /^(?!\d)((?:(?!\s)[$\w\x7f-\uffff])+)([^\n\S]*:(?!:))?/; // Is this a property name?

  CSX_IDENTIFIER = /^(?![\d<])((?:(?!\s)[\.\-$\w\x7f-\uffff])+)/; // Must not start with `<`.
  // Like `IDENTIFIER`, but includes `-`s and `.`s.

  // Fragment: <></>
  CSX_FRAGMENT_IDENTIFIER = /^()>/; // Ends immediately with `>`.

  CSX_ATTRIBUTE = /^(?!\d)((?:(?!\s)[\-$\w\x7f-\uffff])+)([^\S]*=(?!=))?/; // Like `IDENTIFIER`, but includes `-`s.
  // Is this an attribute with a value?

  NUMBER = /^0b[01]+|^0o[0-7]+|^0x[\da-f]+|^\d*\.?\d+(?:e[+-]?\d+)?/i; // binary
  // octal
  // hex
  // decimal

  OPERATOR = /^(?:[-=]>|[-+*\/%<>&|^!?=]=|>>>=?|([-+:])\1|([&|<>*\/%])\2=?|\?(\.|::)|\.{2,3})/; // function
  // compound assign / compare
  // zero-fill right shift
  // doubles
  // logic / shift / power / floor division / modulo
  // soak access
  // range or splat

  WHITESPACE = /^[^\n\S]+/;

  COMMENT = /^\s*###([^#][\s\S]*?)(?:###[^\n\S]*|###$)|^(?:\s*#(?!##[^#]).*)+/;

  CODE = /^[-=]>/;

  MULTI_DENT = /^(?:\n[^\n\S]*)+/;

  JSTOKEN = /^`(?!``)((?:[^`\\]|\\[\s\S])*)`/;

  HERE_JSTOKEN = /^```((?:[^`\\]|\\[\s\S]|`(?!``))*)```/;

  // String-matching-regexes.
  STRING_START = /^(?:'''|"""|'|")/;

  STRING_SINGLE = /^(?:[^\\']|\\[\s\S])*/;

  STRING_DOUBLE = /^(?:[^\\"#]|\\[\s\S]|\#(?!\{))*/;

  HEREDOC_SINGLE = /^(?:[^\\']|\\[\s\S]|'(?!''))*/;

  HEREDOC_DOUBLE = /^(?:[^\\"#]|\\[\s\S]|"(?!"")|\#(?!\{))*/;

  INSIDE_CSX = /^(?:[^\{<])*/; // Start of CoffeeScript interpolation. // Similar to `HEREDOC_DOUBLE` but there is no escaping.
  // Maybe CSX tag (`<` not allowed even if bare).

  CSX_INTERPOLATION = /^(?:\{|<(?!\/))/; // CoffeeScript interpolation.
  // CSX opening tag.

  STRING_OMIT = /((?:\\\\)+)|\\[^\S\n]*\n\s*/g; // Consume (and preserve) an even number of backslashes.
  // Remove escaped newlines.

  SIMPLE_STRING_OMIT = /\s*\n\s*/g;

  HEREDOC_INDENT = /\n+([^\n\S]*)(?=\S)/g;

  // Regex-matching-regexes.
  REGEX = /^\/(?!\/)((?:[^[\/\n\\]|\\[^\n]|\[(?:\\[^\n]|[^\]\n\\])*\])*)(\/)?/; // Every other thing.
  // Anything but newlines escaped.
  // Character class.

  REGEX_FLAGS = /^\w*/;

  VALID_FLAGS = /^(?!.*(.).*\1)[gimsuy]*$/;

  // Match any character, except those that need special handling below.
  // Match `\` followed by any character.
  // Match any `/` except `///`.
  // Match `#` which is not part of interpolation, e.g. `#{}`.
  // Comments consume everything until the end of the line, including `///`.
  HEREGEX = /^(?:[^\\\/#\s]|\\[\s\S]|\/(?!\/\/)|\#(?!\{)|\s+(?:#(?!\{).*)?)*/;

  HEREGEX_OMIT = /((?:\\\\)+)|\\(\s)|\s+(?:#.*)?/g; // Consume (and preserve) an even number of backslashes.
  // Preserve escaped whitespace.
  // Remove whitespace and comments.

  REGEX_ILLEGAL = /^(\/|\/{3}\s*)(\*)/;

  POSSIBLY_DIVISION = /^\/=?\s/;

  // Other regexes.
  HERECOMMENT_ILLEGAL = /\*\//;

  LINE_CONTINUER = /^\s*(?:,|\??\.(?![.\d])|\??::)/;

  STRING_INVALID_ESCAPE = /((?:^|[^\\])(?:\\\\)*)\\(?:(0[0-7]|[1-7])|(x(?![\da-fA-F]{2}).{0,2})|(u\{(?![\da-fA-F]{1,}\})[^}]*\}?)|(u(?!\{|[\da-fA-F]{4}).{0,4}))/; // Make sure the escape isn’t escaped.
  // octal escape
  // hex escape
  // unicode code point escape
  // unicode escape

  REGEX_INVALID_ESCAPE = /((?:^|[^\\])(?:\\\\)*)\\(?:(0[0-7])|(x(?![\da-fA-F]{2}).{0,2})|(u\{(?![\da-fA-F]{1,}\})[^}]*\}?)|(u(?!\{|[\da-fA-F]{4}).{0,4}))/; // Make sure the escape isn’t escaped.
  // octal escape
  // hex escape
  // unicode code point escape
  // unicode escape

  UNICODE_CODE_POINT_ESCAPE = /(\\\\)|\\u\{([\da-fA-F]+)\}/g; // Make sure the escape isn’t escaped.

  LEADING_BLANK_LINE = /^[^\n\S]*\n/;

  TRAILING_BLANK_LINE = /\n[^\n\S]*$/;

  TRAILING_SPACES = /\s+$/;

  // Compound assignment tokens.
  COMPOUND_ASSIGN = ['-=', '+=', '/=', '*=', '%=', '||=', '&&=', '?=', '<<=', '>>=', '>>>=', '&=', '^=', '|=', '**=', '//=', '%%='];

  // Unary tokens.
  UNARY = ['NEW', 'TYPEOF', 'DELETE', 'DO'];

  UNARY_MATH = ['!', '~'];

  // Bit-shifting tokens.
  SHIFT = ['<<', '>>', '>>>'];

  // Comparison tokens.
  COMPARE = ['==', '!=', '<', '>', '<=', '>='];

  // Mathematical tokens.
  MATH = ['*', '/', '%', '//', '%%'];

  // Relational tokens that are negatable with `not` prefix.
  RELATION = ['IN', 'OF', 'INSTANCEOF'];

  // Boolean tokens.
  BOOL = ['TRUE', 'FALSE'];

  // Tokens which could legitimately be invoked or indexed. An opening
  // parentheses or bracket following these tokens will be recorded as the start
  // of a function invocation or indexing operation.
  CALLABLE = ['IDENTIFIER', 'PROPERTY', ')', ']', '?', '@', 'THIS', 'SUPER'];

  INDEXABLE = CALLABLE.concat(['NUMBER', 'INFINITY', 'NAN', 'STRING', 'STRING_END', 'REGEX', 'REGEX_END', 'BOOL', 'NULL', 'UNDEFINED', '}', '::']);

  // Tokens which can be the left-hand side of a less-than comparison, i.e. `a<b`.
  COMPARABLE_LEFT_SIDE = ['IDENTIFIER', ')', ']', 'NUMBER'];

  // Tokens which a regular expression will never immediately follow (except spaced
  // CALLABLEs in some cases), but which a division operator can.

  // See: http://www-archive.mozilla.org/js/language/js20-2002-04/rationale/syntax.html#regular-expressions
  NOT_REGEX = INDEXABLE.concat(['++', '--']);

  // Tokens that, when immediately preceding a `WHEN`, indicate that the `WHEN`
  // occurs at the start of a line. We disambiguate these from trailing whens to
  // avoid an ambiguity in the grammar.
  LINE_BREAK = ['INDENT', 'OUTDENT', 'TERMINATOR'];

  // Additional indent in front of these is ignored.
  INDENTABLE_CLOSERS = [')', '}', ']'];

  // Tokens that, when appearing at the end of a line, suppress a following TERMINATOR/INDENT token
  UNFINISHED = ['\\', '.', '?.', '?::', 'UNARY', 'MATH', 'UNARY_MATH', '+', '-', '**', 'SHIFT', 'RELATION', 'COMPARE', '&', '^', '|', '&&', '||', 'BIN?', 'EXTENDS'];

}).call(this);
