text: module.exports = function (glob, opts) {
    if (typeof glob !== 'string') {
      throw new TypeError('Expected a string');
    }
  
    var str = String(glob);
  
    // The regexp we are building, as a string.
    var reStr = "";
  
    // Whether we are matching so called "extended" globs (like bash) and should
    // support single character matching, matching ranges of characters, group
    // matching, etc.
    var extended = opts ? !!opts.extended : false;
  
    // When globstar is _false_ (default), '/foo/*' is translated a regexp like
    // '^\/foo\/.*$' which will match any string beginning with '/foo/'
    // When globstar is _true_, '/foo/*' is translated to regexp like
    // '^\/foo\/[^/]*$' which will match any string beginning with '/foo/' BUT
    // which does not have a '/' to the right of it.
    // E.g. with '/foo/*' these will match: '/foo/bar', '/foo/bar.txt' but
    // these will not '/foo/bar/baz', '/foo/bar/baz.txt'
    // Lastely, when globstar is _true_, '/foo/**' is equivelant to '/foo/*' when
    // globstar is _false_
    var globstar = opts ? !!opts.globstar : false;
  
    // If we are doing extended matching, this boolean is true when we are inside
    // a group (eg {*.html,*.js}), and false otherwise.
    var inGroup = false;
  
    // RegExp flags (eg "i" ) to pass in to RegExp constructor.
    var flags = opts && typeof( opts.flags ) === "string" ? opts.flags : "";
  
    var c;
    for (var i = 0, len = str.length; i < len; i++) {
      c = str[i];
  
      switch (c) {
      case "\\":
      case "/":
      case "$":
      case "^":
      case "+":
      case ".":
      case "(":
      case ")":
      case "=":
      case "!":
      case "|":
        reStr += "\\" + c;
        break;
  
      case "?":
        if (extended) {
          reStr += ".";
  	    break;
        }
  
      case "[":
      case "]":
        if (extended) {
          reStr += c;
  	    break;
        }
  
      case "{":
        if (extended) {
          inGroup = true;
  	    reStr += "(";
  	    break;
        }
  
      case "}":
        if (extended) {
          inGroup = false;
  	    reStr += ")";
  	    break;
        }
  
      case ",":
        if (inGroup) {
          reStr += "|";
  	    break;
        }
        reStr += "\\" + c;
        break;
  
      case "*":
        // Move over all consecutive "*"'s.
        // Also store the previous and next characters
        var prevChar = str[i - 1];
        var starCount = 1;
        while(str[i + 1] === "*") {
          starCount++;
          i++;
        }
        var nextChar = str[i + 1];
  
        if (!globstar) {
          // globstar is disabled, so treat any number of "*" as one
          reStr += ".*";
        } else {
          // globstar is enabled, so determine if this is a globstar segment
          var isGlobstar = starCount > 1                      // multiple "*"'s
            && (prevChar === "/" || prevChar === undefined)   // from the start of the segment
            && (nextChar === "/" || nextChar === undefined)   // to the end of the segment
  
          if (isGlobstar) {
            // it's a globstar, so match zero or more path segments
            reStr += "(?:[^/]*(?:\/|$))*";
            i++; // move over the "/"
          } else {
            // it's not a globstar, so only match one path segment
            reStr += "[^/]*";
          }
        }
        break;
  
      default:
        reStr += c;
      }
    }
  
    // When regexp 'g' flag is specified don't
    // constrain the regular expression with ^ & $
    if (!flags || !~flags.indexOf('g')) {
      reStr = "^" + reStr + "$";
    }
  
    return new RegExp(reStr, flags);
  };
  