code: function(inlines) {
    var m;
    if ((m = this.match(reMain))) {
      inlines.push({ t: 'Str', c: m });
      return m.length;
    } else {
      return 0;
    }
  }
docs: Parse a run of ordinary characters, or a single character with a special meaning in markdown, as a plain string, adding to inlines.